331 core topics
+ 85 prerequisite topics taught
as needed · approximately 127 hours of instruction
including spaced review
An adaptive diagnostic (up to
40 questions) places the student on the course's knowledge
graph - topics already known are credited, and instruction begins exactly
at the learning frontier. Every topic is taught with a worked-example
lesson and auto-graded practice; a topic is mastered at
75%+ and then maintained through spaced reviews on an
expanding schedule. Mixed checks follow every 6 lessons;
each unit ends with a 12-item quiz, and course-wide assessments appear at
25%, 50%, 75%, and 100% mastery. Prerequisite gaps below the course are detected and taught rather
than skipped, so completion certifies the whole tower, not just the top.
| The Limit Definition of the Derivative
[M] |
The derivative is the limit of average rates of change. |
| Derivatives Graphically
[M] |
Reading slopes off a graph. |
| The Power Rule
[M] |
d/dx xⁿ = n·xⁿ⁻¹ for any real n. |
| Sum & Constant-Multiple Rules
[M] |
Differentiate term by term. |
| The Product Rule
[M] |
(fg)′ = f′g + fg′. |
| The Quotient Rule
[M] |
(f/g)′ = (f′g − fg′)/g². |
| Derivatives of Trig Functions
[M] |
d/dx sin x = cos x, d/dx cos x = −sin x, d/dx tan x = sec²x. |
| Derivatives of Exponentials & Logs
[M] |
eˣ is its own derivative; (ln x)′ = 1/x. |
| The Chain Rule
[H] |
d/dx f(g(x)) = f′(g(x)) · g′(x). |
| Combining Differentiation Rules
[H] |
Product, quotient and chain rules together. |
| Implicit Differentiation
[H] |
Differentiating equations that mix x and y. |
| Derivatives of Inverse Trig
[M] |
(arcsin x)′ = 1/√(1−x²), (arctan x)′ = 1/(1+x²). |
| Derivatives of Inverse Functions
[M] |
(f⁻¹)′(b) = 1 / f′(f⁻¹(b)). |
| Higher-Order Derivatives
[M] |
Differentiating again: f″, f‴, … |
| Differentiability & Continuity
[M] |
Differentiable ⇒ continuous, but not conversely. |
| Tangent Lines & Linear Approximation
[M] |
The tangent line is the best local linear stand-in for f. |
| Motion: Position, Velocity, Acceleration
[M] |
v = s′, a = v′; at rest when v = 0. |
| Related Rates
[H] |
Differentiating a geometric relationship with respect to time. |
| Critical Points & Extrema
[M] |
Where f′ = 0 or is undefined - the candidates for extrema. |
| The Mean Value Theorem
[M] |
Somewhere, instantaneous rate equals average rate. |
| Increasing & Decreasing Intervals
[M] |
Sign of f′ decides the direction of f. |
| Concavity & Inflection Points
[M] |
f″ > 0 bends up, f″ < 0 bends down. |
| Curve Sketching & f, f', f''
[M] |
Reading the shape of f from its derivatives. |
| Optimization
[H] |
Maximizing or minimizing with calculus. |
| L'Hôpital's Rule
[M] |
For 0/0 or ∞/∞, differentiate top and bottom. |
| Indeterminate Forms
[M] |
0·∞ and repeated applications. |
| Antiderivatives
[M] |
Reversing differentiation: the power rule backwards. |
| Antiderivatives: Trig & Exponential
[M] |
∫cos = sin, ∫sin = −cos, ∫eˣ = eˣ, ∫1/x = ln|x|. |
| Riemann Sums
[M] |
Approximating area with rectangles. |
| The Trapezoidal Rule
[M] |
Averaging left and right sums. |
| Properties of Definite Integrals
[M] |
Linearity, additivity, and orientation. |
| The Fundamental Theorem: Evaluating Integrals
[M] |
∫ₐᵇ f = F(b) − F(a). |
| Accumulation Functions & FTC Part 1
[H] |
d/dx ∫ₐˣ f(t) dt = f(x). |
| u-Substitution
[H] |
The chain rule in reverse. |
| Integration by Parts (BC)
[H] |
∫u dv = uv − ∫v du. |
| Partial Fractions (BC)
[H] |
Splitting rational functions to integrate them. |
| Improper Integrals (BC)
[H] |
Integrals to infinity, defined by limits. |
| Integrals Yielding Inverse Trig
[H] |
1/(1+x²) → arctan, 1/√(1−x²) → arcsin. |
| Convergence of Sequences (BC)
[M] |
A sequence converges if aₙ approaches a limit. |
| Geometric Series (BC)
[M] |
Σarⁿ = a/(1−r) when |r| < 1. |
| The nth-Term Test (BC)
[M] |
If terms don't go to 0, the series diverges - but 0 proves nothing. |
| Integral Test & p-Series (BC)
[M] |
Σ1/nᵖ converges iff p > 1. |
| Comparison Tests (BC)
[M] |
Compare with a series you already understand. |
| Alternating Series (BC)
[M] |
Alternating + decreasing to 0 ⇒ converges. |
| Alternating Series Error Bound (BC)
[H] |
|error| ≤ first omitted term. |
| The Ratio Test (BC)
[H] |
L = lim|aₙ₊₁/aₙ|: L<1 converges, L>1 diverges, L=1 says nothing. |
| Absolute vs Conditional Convergence (BC)
[M] |
Does it still converge with all terms made positive? |
| Radius of Convergence (BC)
[H] |
The ratio test gives |x − c| < R. |
| Interval of Convergence (BC)
[H] |
Check both endpoints separately. |
| Taylor Polynomials (BC)
[H] |
Matching derivatives at a point: Pₙ(x) = Σ f⁽ᵏ⁾(a)(x−a)ᵏ/k!. |
| Taylor & Maclaurin Series (BC)
[H] |
The big four: eˣ, sin x, cos x, 1/(1−x). |
| Manipulating Known Series (BC)
[H] |
Substitute, multiply, differentiate, integrate known series. |
| Lagrange Error Bound (BC)
[H] |
|Rₙ| ≤ M|x−a|ⁿ⁺¹/(n+1)!. |
| Classifying Discontinuities
[M] |
Removable, jump, or infinite - three ways continuity can fail. |
| Limits of Piecewise Functions
[M] |
One-sided limits pick the piece the input comes from. |
| Continuity on an Interval & Existence
[M] |
Match the pieces; then let the IVT do the existence work. |
| The Extreme Value Theorem
[M] |
Continuous on a closed interval ⇒ an absolute max and min exist. |
| The First-Derivative Test
[M] |
Where f′ switches + → − is a max; − → + is a min. |
| The Second-Derivative Test
[M] |
At a critical point, concavity settles max vs. min. |
| The Candidates Test for Absolute Extrema
[H] |
On [a, b], the absolute extremes hide among critical points and endpoints. |
| Reasoning Across f, f′ and f″
[M] |
Given one graph, deduce the sign story of the others. |
| Linearization & Differentials
[M] |
L(x) = f(a) + f′(a)(x − a); concavity says over or under. |
| Indeterminate Forms in Depth
[H] |
Turn 0·∞, ∞−∞ and 1^∞ into a quotient, then apply L'Hôpital. |
| Interpreting the Derivative in Context
[M] |
f′(a) is a rate: its units are (units of f) per (unit of x). |
| Rates of Change in Applied Contexts
[M] |
Instantaneous rate is a derivative; average rate is a difference quotient. |
| Riemann Sums in Sigma Notation
[M] |
Package a Riemann sum as Σ f(x_i)·Δx and use summation formulas. |
| The Definite Integral as a Limit
[M] |
Send n → ∞ and the Riemann sum becomes the definite integral. |
| Over- and Under-Estimates of Sums
[M] |
Monotonicity fixes left/right; concavity fixes the trapezoid. |
| Area Between Curves (with respect to y)
[M] |
When curves are functions of y, integrate (right − left) dy. |
| Volumes About a Non-Axis Line
[H] |
Shift the radii: distance to y = k, not to the axis. |
| Accumulation Functions & FTC Analysis
[H] |
g(x) = ∫ₐˣ f: its slope is f, so f's sign shapes g. |
| Reasoning with Slope Fields
[M] |
Read where slopes are zero, and whether they depend on x or y. |
| Interpreting a Definite Integral in Context
[M] |
∫ of a rate is a net change - with the rate's units × x's units. |
| Average Value vs. Average Rate of Change
[M] |
One is an integral ÷ length; the other is a difference ÷ length. |
| Total Distance vs. Displacement
[H] |
Displacement integrates v; distance integrates |v|. |
| Setting Up a Differential Equation
[M] |
Translate 'rate proportional to …' into dy/dt = k·(…). |
| Combining Limits with the Limit Laws
[H] |
The limit of a sum, product, or quotient is that operation on the limits. |
| Limits by Direct Substitution
[H] |
Where a function is continuous, the limit is just the value there. |
| 0/0 Limits by Non-Monic Factoring
[H] |
Factor the shared (x - c) from top and bottom, cancel, then substitute. |
| 0/0 Limits with Cubes and Higher Powers
[H] |
Difference-of-powers factoring cancels the zero: xⁿ - aⁿ has factor x - a. |
| 0/0 Limits with Compound Fractions
[H] |
Combine the little fractions over a common denominator, then cancel. |
| Conjugate Limits (Radical in the Denominator)
[H] |
Multiply top and bottom by the denominator's conjugate to clear the 0/0. |
| Conjugate Limits with a Rational Value
[H] |
Conjugate the radical numerator; the leftover root evaluates to a number. |
| One-Sided Limits of Absolute-Value Functions
[H] |
|x - c|/(x - c) is +1 on the right of c and -1 on the left. |
| One-Sided Limits of Step Functions
[H] |
The floor function drops by 1 across each integer: a jump discontinuity. |
| Limits at Infinity with Radicals
[H] |
For large |x|, √(ax² + ...) behaves like √a·|x|; watch the sign at -∞. |
| Growth Rates: Exponential vs Polynomial vs Log
[H] |
As x → ∞, exponentials beat any power, and any power beats logarithms. |
| Counting Horizontal Asymptotes
[H] |
Each finite limit as x → +∞ and as x → -∞ gives one horizontal asymptote. |
| Bounded-Over-Growing Limits at Infinity
[H] |
A bounded numerator divided by something growing to ∞ tends to 0. |
| Identifying Vertical Asymptotes
[H] |
A denominator zero that does NOT cancel is a vertical asymptote; one that cancels is a hole. |
| Sign of a One-Sided Infinite Limit
[H] |
Near an asymptote, count the signs of every factor to choose +∞ or -∞. |
| Infinite Limits of ln, tan, and Reciprocal Powers
[H] |
Infinite limits of ln x, tan x, and 1/xⁿ, where each grows without bound at the given point. |
| The Squeeze Theorem with Computed Bounds
[H] |
When the two bounding functions meet at x = c, evaluate them to get L. |
| The Squeeze Theorem on Bounded Oscillation
[H] |
A factor going to 0 times a bounded oscillation is squeezed to 0. |
| The (1 - cos)/x² Limit
[H] |
As x → 0, (1 - cos x)/x² → 1/2; scaling the angle scales by the square. |
| Products and Quotients of sin, tan at 0
[H] |
Rewrite each factor as sin(kx)/(kx) or tan(kx)/(kx), each → 1, then read off the constants. |
| Trig Limits Needing a Substitution
[H] |
A shift like u = x - π turns an unfamiliar trig limit into a standard one. |
| Classifying Discontinuities of Rational Functions
[H] |
A canceling factor gives a removable hole; a surviving one gives an infinite discontinuity. |
| Counting Discontinuities
[H] |
Every zero of the original denominator is a discontinuity; canceling ones are the holes. |
| Which Continuity Condition Fails
[H] |
Continuity needs f(c) defined, the limit to exist, and the two to agree. |
| Gluing Pieces with a Coefficient Unknown
[H] |
Set the two pieces equal at the boundary and solve for the unknown coefficient. |
| Filling a Removable Hole
[H] |
Cancel the common factor, then evaluate the simplified form to get k. |
| Where Is a Function Continuous
[H] |
Rational functions break at denominator zeros; roots need the inside ≥ 0. |
| Continuity on an Interval
[H] |
The interval of continuity is the domain: root needs ≥ 0, log needs > 0. |
| Counting Guaranteed Roots with the IVT
[H] |
Each sign change between consecutive points guarantees at least one root. |
| Guaranteeing a Value with the IVT
[H] |
The IVT only guarantees values that lie between f(a) and f(b). |
| The IVT in Applied Contexts
[H] |
A continuously changing real quantity attains every value between its endpoints. |
| Limit Definition on a General Quadratic
[H] |
Expand f(a + h), subtract f(a), divide by h, cancel, then let h → 0. |
| Recognizing a Difference Quotient
[H] |
Match lim (f(a + h) - f(a))/h to its f and a by reading the base and the power. |
| Limit Definition for Roots and Reciprocals
[H] |
Rationalize (for √x) or combine over a common denominator (for 1/x), then let h → 0. |
| The x → a Form of the Derivative Limit
[H] |
f′(a) = lim (f(x) - f(a))/(x - a); factor out (x - a) and substitute. |
| Two-Sided Limit vs the Function Value
[H] |
When both one-sided limits agree, the limit is their common value - not f(c). |
| Limits of Composite Functions
[H] |
If the outer function is continuous, take the limit inside first. |
| Power Rule for Negative Exponents
[H] |
Rewrite 1/x^n as x^(-n), then bring the negative exponent down. |
| Power Rule for Rational Exponents
[H] |
d/dx x^(p/q) = (p/q) x^((p-q)/q) - subtract 1 from the fraction. |
| Rewrite Radicals and Reciprocals, then Differentiate
[H] |
Turn every root and reciprocal into a power of x before applying the rule. |
| Differentiating a Polynomial (the Derivative Function)
[H] |
Differentiate term by term to get f' as a function, then simplify. |
| Product Rule: Polynomial Times Polynomial
[H] |
(fg)' = f'g + fg'; differentiate each factor, keep the other whole. |
| Product Rule with a Radical Factor
[H] |
One factor is a root: differentiate it as x^(1/2) inside the product rule. |
| Product Rule for Three Factors
[H] |
(fgh)' = f'gh + fg'h + fgh' - one term per factor differentiated. |
| Quotient Rule on Rational Functions
[H] |
(f/g)' = (f'g - fg')/g^2; the numerator collapses to a constant here. |
| Quotient Rule with a Trig Function
[H] |
Numerator or denominator is trig: apply (f'g - fg')/g^2 with cos/-sin. |
| Evaluating a Quotient-Rule Derivative
[H] |
Differentiate with the quotient rule, then substitute the x-value. |
| Chain Rule: a Power of a Polynomial
[H] |
d/dx u^n = n u^(n-1) u'; the inner derivative is the outside factor. |
| Chain Rule: Trig of a Polynomial Argument
[H] |
d/dx sin(u) = cos(u) u'; the argument's derivative multiplies on. |
| Chain Rule: Exponential of a Function
[H] |
d/dx e^u = e^u u'; the exponential is reproduced, times u'. |
| Chain Rule: Logarithm of a Function
[H] |
d/dx ln(u) = u'/u - the inside derivative over the inside. |
| The Chain Rule Twice (Nested Compositions)
[H] |
Peel one layer at a time: outer, then middle, then inner. |
| Implicit Differentiation: Solving for dy/dx
[H] |
Differentiate every term (each y gives a y' factor), then solve for y'. |
| Implicit Differentiation at a Point
[H] |
Find dy/dx implicitly, then substitute both coordinates of the point. |
| Implicit Differentiation of a Product of Powers
[H] |
Differentiate x^m y^n as a product; the a on the right has derivative 0. |
| Derivative of a^x
[H] |
d/dx a^x = a^x ln a - the base exponential picks up a factor of ln a. |
| Derivative of log_a(x)
[H] |
d/dx log_a x = 1/(x ln a) - divide the natural-log rule by ln a. |
| Derivative of a^(g(x))
[H] |
d/dx a^u = a^u (ln a) u' - base rule times the argument's derivative. |
| Logarithmic Differentiation of x^(ax)
[H] |
Take ln of both sides, differentiate implicitly, then multiply back by f. |
| Derivatives of tan, sec, csc, and cot
[H] |
The four reciprocal-family rules, with the two minus signs on csc and cot. |
| Trig Derivatives with a Coefficient Argument
[H] |
d/dx trig(kx) multiplies the basic rule by the inside derivative k. |
| Products with Trig Functions
[H] |
Combine the product rule with a trig derivative. |
| Exact Trig Derivative Values at Special Angles
[H] |
Differentiate, then evaluate with exact unit-circle values. |
| Derivatives of arccos and arccot
[H] |
The co-inverse rules are the negatives of arcsin's and arctan's. |
| Inverse Trig with the Chain Rule
[H] |
d/dx arctan(u) = u'/(1+u^2); the inside derivative multiplies on top. |
| Evaluating Inverse-Trig Derivatives
[H] |
Substitute into 1/(1+x^2) (arctan) or -1/(1+x^2) (arccot). |
| The Second Derivative as a Function
[H] |
Differentiate twice; report f'' as an expression in x. |
| n-th Derivative Patterns
[H] |
Repeated differentiation of e^(kx), ln x and 1/x follows a clean pattern. |
| Second Derivatives of Sine and Cosine
[H] |
Two derivatives of sin(kx) return -k^2 times the original sinusoid. |
| Making a Piecewise Function Differentiable
[H] |
Differentiable needs BOTH matching slopes and matching values at the join. |
| Corners, Cusps, and Vertical Tangents
[H] |
Continuous but not differentiable: corner, cusp, or vertical tangent. |
| Differentiability Implies Continuity (Not Conversely)
[H] |
Differentiable forces continuous; continuous does not force differentiable. |
| Estimating a Derivative from a Table
[H] |
Approximate f'(x1) by the symmetric difference (f(x2)-f(x0))/(x2-x0). |
| Reading f'(x) off a Piecewise-Linear Graph
[H] |
On a straight segment, f'(x) is that segment's constant slope. |
| The Chain Rule from a Table of Values
[H] |
h'(a) = f'(g(a)) g'(a): look up f' at the INNER output g(a), not at a. |
| Related Rates: Expanding Ripple
[H] |
Differentiate the circle relation, then solve for the wanted rate. |
| Related Rates: Inflating Balloon
[H] |
Differentiate the sphere formula; a radius rate and a volume rate trade. |
| Related Rates: Draining/Filling Cone
[H] |
Use similar triangles to reduce V to one variable, then differentiate. |
| Related Rates: Walking Shadow
[H] |
Similar triangles relate shadow length to distance; differentiate. |
| Related Rates: Sliding-Ladder Triangle Area
[H] |
Combine the ladder's dy/dt with the product rule on A = (1/2)xy. |
| Related Rates: Differentiating the Relation
[H] |
Every variable that changes with time carries a chain-rule factor. |
| Differentials: Estimating a Change
[H] |
dy = f'(x) dx estimates a small change from the derivative. |
| Linear Approximation of Roots & Reciprocals
[H] |
L(x) = f(a) + f'(a)(x - a) with a chosen so f(a) is exact. |
| Differentials: Relative Error Propagation
[H] |
For a power law y = x^n, the relative error multiplies by n. |
| L'Hopital: 0/0 Trigonometric Limits
[H] |
Confirm 0/0, then differentiate top and bottom (sometimes twice). |
| L'Hopital: Infinity Over Infinity
[H] |
For a rational or radical quotient, the leading terms decide. |
| Recognizing Indeterminate Forms
[H] |
L'Hopital needs 0/0 or infinity/infinity - check before applying. |
| Mean Value Theorem: Solving for c
[H] |
Set f'(c) equal to the average rate, then solve for c in (a, b). |
| Rolle's Theorem: Solving for c
[H] |
Equal endpoint values force a flat spot; solve f'(c) = 0 inside. |
| Bounding a Function with the MVT
[H] |
f(b) - f(a) = f'(c)(b - a), so derivative bounds bound the change. |
| Rolle & MVT: Checking the Hypotheses
[H] |
Continuity on [a,b], differentiability on (a,b), and (Rolle) equal ends. |
| First-Derivative Test with a Repeated Factor
[H] |
A squared factor gives a critical point with no sign change - no extremum. |
| Counting Critical Points
[H] |
Count zeros of f' AND points where f' is undefined; a double root is one. |
| Critical Points via the Product/Quotient Rule
[H] |
Differentiate the product or quotient, factor, and set equal to zero. |
| Second Derivative at a Critical Point
[H] |
Find the critical points from f', then evaluate f'' there. |
| Second-Derivative Test: Classifying Extrema
[H] |
f'' > 0 means min, f'' < 0 means max, f'' = 0 means inconclusive. |
| Absolute Extrema: The Candidates Test
[H] |
Evaluate f at every interior critical point and both endpoints. |
| Absolute Extrema: Where They Occur
[H] |
The winner can be an endpoint - compare all candidates, do not assume. |
| Absolute Extrema of a Rational Function
[H] |
Same Candidates Test - just differentiate the quotient to find the crit. |
| Optimization: Fence Against a River
[H] |
One free side changes the constraint: fence = 2x + y, area = x(L - 2x). |
| Optimization: Open Box from a Sheet
[H] |
V(x) = x(a - 2x)^2; the maximizing cut is x = a/6. |
| Optimization: Minimum-Cost Enclosure
[H] |
Fix the area constraint, write cost as C(x), minimize with calculus. |
| Optimization: Constrained Two-Number Problems
[H] |
Use the constraint to reduce to one variable, then optimize. |
| Optimization: Building the Objective Function
[H] |
Translate the constraint into a one-variable formula for what to optimize. |
| Motion: Speeding Up or Slowing Down
[H] |
Speeding up when velocity and acceleration share a sign. |
| Motion: Total Distance via Turning Points
[H] |
Split at the times v = 0, then add the absolute position changes. |
| Motion: Maximum Velocity
[H] |
Velocity is extreme where acceleration is zero (or at an endpoint). |
| Inflection Points of a Quartic
[H] |
Solve f'' = 0 and confirm the sign of f'' actually flips. |
| Concavity Intervals of a Cubic
[H] |
Concave up where f'' > 0; a cubic switches once at its inflection. |
| Verifying an Inflection Point
[H] |
f'' = 0 is necessary but not sufficient - the sign must actually flip. |
| Counting Inflection Points from f''
[H] |
Count the sign changes of f'' - simple roots flip, even-power roots do not. |
| Antiderivative of a Coefficient Times a Power
[H] |
A constant multiple rides along: raise the power by one and divide. |
| Antiderivative of a Polynomial (as a Function)
[H] |
Antidifferentiate term by term; the sum rule lets each power act alone. |
| Antiderivative of a Negative Power
[H] |
The power rule still works for x^(-n) (as long as n is not 1). |
| Antiderivative of a Radical (Rational Power)
[H] |
Write the root as a fractional power, then add one to the exponent. |
| Reciprocal-Trig Antiderivatives
[H] |
Read the sec/csc derivative table backward. |
| Antiderivative of an Exponential Base a
[H] |
For a base other than e, divide by ln a. |
| FTC: A Polynomial Over a General Interval
[H] |
Antidifferentiate, then subtract F(a) from F(b) - with real endpoints. |
| FTC: Trig Integrals at Exact Angles
[H] |
Antidifferentiate the sinusoid, then read an exact unit-circle value. |
| FTC: Exponential Integrals
[H] |
The antiderivative of e^(kx) is e^(kx)/k; then subtract the endpoints. |
| FTC: The 1/x Integral (Logarithms)
[H] |
The antiderivative of 1/x is ln|x|, so the integral is a difference of logs. |
| FTC: Definite Integral of a Negative Power
[H] |
Antidifferentiate x^(-p) to x^(1-p)/(1-p), then subtract the endpoints. |
| FTC: Integrating an Absolute Value
[H] |
Split at the corner where the inside changes sign; add two triangle areas. |
| u-Substitution: Indefinite Polynomial Form
[H] |
The lone x supplies half of du = 2x dx; integrate u^n, then divide. |
| u-Substitution: Definite Polynomial Form
[H] |
Change the limits with u, then evaluate in u - no need to resubstitute. |
| u-Substitution: Powers of Sine or Cosine
[H] |
Let u be the base trig function; its derivative is the leftover factor. |
| u-Substitution: Gaussian-Type Exponential
[H] |
Let u be the exponent; the outside x is (part of) du. |
| u-Substitution: The ln|u| Pattern
[H] |
When the top is the derivative of the bottom, the integral is a log. |
| u-Substitution With a Radical (Change of Limits)
[H] |
Let u be the inside of the root; the outer x completes du. |
| FTC Part 1: The Derivative Function
[H] |
d/dx of an accumulation function just hands back the integrand at x. |
| FTC Part 1 With the Chain Rule
[H] |
Upper limit u(x): evaluate f at u, then multiply by u'. |
| FTC Part 1: Variable Lower Limit
[H] |
x on the bottom flips the sign: g'(x) = -f(x). |
| FTC Part 1: Both Limits Are Functions
[H] |
Top minus bottom: f(upper)*upper' - f(lower)*lower'. |
| FTC Part 1: Shape of the Accumulation
[H] |
Since g' = f, the sign and slope of f dictate g's shape. |
| Midpoint Riemann Sum From a Function
[H] |
Sample each subinterval at its center, not an endpoint. |
| Left/Right Riemann Sum From a Function
[H] |
Build the sample heights yourself from the formula, not a table. |
| Trapezoidal Rule From a Function
[H] |
Half-weight the two ends, full-weight every interior point. |
| A Riemann-Sum Limit as an Integral
[H] |
Read off a, b, and f from the width and the sample point. |
| Expressing an Integral as a Riemann Sum
[M] |
Width is (b - a)/n; the right endpoint starts at a and steps by that width. |
| Odd/Even Symmetry of Definite Integrals
[H] |
Odd terms vanish over [-a, a]; even terms double the half-integral. |
| Splitting Off an Adjacent Interval
[H] |
Additivity rearranged: the piece from b to c is the whole minus the first. |
| Linearity Across Two Functions
[H] |
The integral of a linear combination is the same combination of integrals. |
| Adding a Constant to the Integrand
[H] |
Adding c raises the integral by c times the interval length. |
| A Definite Integral as a Geometric Area
[H] |
y = sqrt(r^2 - x^2) is a semicircle; use the circle-area formula. |
| By Parts: Polynomial Times Exponential
[H] |
Let u = x (it differentiates away) and dv = e^(ax) dx. |
| By Parts: Polynomial Times Trig
[H] |
Let u = x; dv is the sinusoid, which integrates cleanly. |
| By Parts: Logarithmic Integrands
[H] |
Let u = ln x (it differentiates to 1/x) and dv be the power. |
| By Parts: Exact Definite Values
[H] |
Find the antiderivative by parts, then evaluate at the limits. |
| Area Between a Line and a Parabola
[H] |
Integrate (top - bottom) between the two intersection points. |
| Area When Curves Cross (Splitting the Integral)
[H] |
Where the top and bottom curve swap, split and add the pieces. |
| Area Between Trigonometric Curves
[H] |
Integrate the difference of the trig curves; cos is above sin on [0, pi/4]. |
| Area Between Curves (Integrating in y)
[H] |
When curves are x = g(y), integrate (right - left) dy. |
| Area of a Sideways-Parabola Region
[H] |
A leftward parabola meets x = 0 at y = +-a; integrate its width in y. |
| Disc Method About the x-axis
[H] |
Each disc has radius equal to the curve; V = pi * integral of R^2 dx. |
| Disc Method About the y-axis
[H] |
Slice in y: radius is x = sqrt(y), so V = pi * integral of y dy. |
| Washer Method About the x-axis
[H] |
Outer radius minus inner radius: V = pi * integral of (R^2 - r^2) dx. |
| Washer Method About the y-axis
[H] |
Slice in y: outer radius sqrt(y), inner radius y/a. |
| Washers About a Horizontal Line
[H] |
Measure both radii from the line y = c, not from the axis. |
| Cylindrical Shells About the y-axis
[H] |
A shell has radius x and height f(x): V = 2*pi * integral of x f(x) dx. |
| Cylindrical Shells About the x-axis
[H] |
Slice in y: shell radius y, height (k - sqrt(y)). |
| Cylindrical Shells About a Vertical Line
[H] |
Shell radius is the distance c - x to the line x = c. |
| Square Cross-Sections on a Two-Curve Base
[H] |
The side of each square is the gap between the two curves. |
| Semicircular Cross-Sections
[H] |
Semicircle on diameter w has area (pi/8) w^2. |
| Equilateral-Triangle Cross-Sections
[H] |
Equilateral triangle of side s has area (sqrt3/4) s^2. |
| Isosceles-Right-Triangle Cross-Sections
[H] |
Leg equal to base width w gives area (1/2) w^2. |
| Cross-Sections Perpendicular to the y-axis
[H] |
Slice in y: the base width is x = sqrt(y), so a square has area y. |
| Square Cross-Sections on a Circular Base
[H] |
At position x the chord has length 2 sqrt(R^2 - x^2); square it. |
| Average Value of a Quadratic
[H] |
Average value is the integral over [a, b] divided by (b - a). |
| Average Value of a Trigonometric Function
[H] |
Average value pulls a 1/(b-a) factor out front; here 1/pi. |
| The Mean Value Theorem for Integrals
[H] |
Solve f(c) = average value for c inside the interval. |
| Average Value of a Rate
[H] |
Average rate = (net change)/(elapsed time) = integral of r, over the time. |
| Net Change from a Polynomial Rate
[H] |
Net change is the definite integral of the rate. |
| Final Amount from a Starting Value
[H] |
Final amount = initial amount + integral of the rate. |
| Net Change with Competing Rates
[H] |
Net change integrates (inflow rate - outflow rate). |
| Interpreting and Naming a Net Change
[H] |
Integrating a rate gives a total, with the rate's numerator units. |
| Displacement from a Quadratic Velocity
[H] |
Displacement is the signed integral of velocity. |
| Total Distance from a Quadratic Velocity
[H] |
Total distance integrates |v|, so split where v changes sign. |
| Position from Velocity and an Initial Value
[H] |
s(T) = s(0) + integral of v from 0 to T. |
| Speeding Up vs Slowing Down
[H] |
Speeding up when velocity and acceleration share a sign. |
| Average Velocity vs Average Speed
[H] |
Average velocity uses displacement; average speed uses total distance. |
| Exact Arc Length of a Rational Curve
[H] |
For this curve 1 + (y')^2 is a perfect square, so the root simplifies. |
| Arc Length of a Slanted Line
[H] |
A line's length is sqrt(1 + m^2) times the run. |
| Setting Up the Arc-Length Integrand
[H] |
Differentiate, square, add 1, then take the square root. |
| Choosing the Integral for an Area
[H] |
Use the full interval between intersections and top minus bottom. |
| Choosing a Volume Method
[H] |
Match discs/washers vs shells to the axis and the slice direction. |
| Verifying: Which Function Solves It
[H] |
Differentiate each candidate and substitute; only a genuine solution fits. |
| Verifying: Constant of a Shifted Solution
[H] |
Plug the initial condition into the general solution and solve for C. |
| Verifying: Constant of an Implicit Solution
[H] |
An implicit solution is a level curve; the initial point fixes its level. |
| Verifying: Evaluating a Solution Family
[H] |
Use the initial value to find C, then substitute the requested x. |
| Separable: General Antiderivative Solution
[H] |
When dy/dx depends on x only, y is just an antiderivative plus C. |
| Separable: Solving Explicitly for y
[H] |
Separate, integrate both sides, use the initial condition, then isolate y. |
| Separable: A Reciprocal Right Side
[H] |
Clear the reciprocal by cross-multiplying the differentials first. |
| Separable: Exponential of a Square
[H] |
Dividing by y gives dy/y = f(x)dx; the integral of dy/y is ln|y|. |
| Separable: A Trigonometric Rate
[H] |
Same recipe, with a trig antiderivative: the integral of cos x is sin x. |
| Separable: Implicit-Solution Constant
[H] |
Separate to an implicit relation, then let the point fix the constant. |
| Separable: Evaluating a Particular Solution
[H] |
dy/dx = y/x separates to ln|y| = ln|x| + C, a line through the origin. |
| Slope Fields: Slope at a Point
[H] |
The slope of a segment is just dy/dx evaluated at that point. |
| Slope Fields: Matching a Field to an Equation
[H] |
Read where segments are horizontal and whether they vary with x or y. |
| Slope Fields: Where Segments Are Horizontal
[H] |
Horizontal segments occur exactly on the curve F(x, y) = 0. |
| Slope Fields: Equilibrium Solutions
[H] |
Constant solutions are the y-values where dy/dx is zero for all x. |
| Slope Fields: Long-Run Behavior
[H] |
Track the sign of dy/dx on each side of an equilibrium to see the drift. |
| Slope Fields: Concavity of a Solution Curve
[H] |
Differentiate dy/dx again (chain rule) to read a solution's concavity. |
| Exponential Models: Recovering the Rate Constant
[H] |
From y0·e^(kt) = (factor)·y0, take a logarithm to solve for k. |
| Exponential Models: Evaluating the Solution
[H] |
Solve dP/dt = kP as P = P0·e^(kt), then substitute the time. |
| Exponential Models: Doubling Time
[H] |
Doubling means e^(kt) = 2, so t = ln 2 / k. |
| Exponential Models: Half-Life and k
[H] |
Half-life means e^(-kH) = 1/2, so k = ln 2 / H. |
| Exponential Models: Relative Rate as k
[H] |
In dB/dt = kB, k is the constant relative (per-unit) growth rate. |
| Exponential Models: Continuous Decay Amount
[H] |
Count how many reduction periods fit in the time, then divide repeatedly. |
| Newton's Cooling: Evaluating the Model
[H] |
Substitute the time into T = T_s + (T_0 - T_s)e^(kt). |
| Newton's Cooling: Limiting Temperature
[H] |
As t grows the exponential dies, leaving the surrounding temperature. |
| Newton's Cooling: Recovering k
[H] |
Subtract the ambient temperature, form the ratio, then take a log. |
| Newton's Cooling: Solving for a Time
[H] |
Set T equal to the target, isolate the exponential, then take a log. |
| Logistic: Carrying Capacity from aP - bP^2
[H] |
Factor dP/dt = aP - bP^2 = bP(a/b - P); the capacity is a/b. |
| Logistic: Fastest-Growth Population
[H] |
The parabola aP - bP^2 peaks at P = a/(2b), which is half the capacity. |
| Logistic: Maximum Growth Rate
[H] |
The peak rate is the vertex height a^2/(4b), reached at P = L/2. |
| Logistic: Sign of the Growth Rate
[H] |
Below L the rate is positive; above L it is negative; solutions tend to L. |
| Logistic: Rate at a Given Population
[H] |
Just substitute the population into the rate expression aP - bP^2. |
| Logistic: Inflection of the Solution Curve
[H] |
The S-curve changes concavity where growth is fastest, at P = L/2. |
| Euler's Method: One Step
[H] |
One step rides the tangent: y_new = y + h·f(x, y). |
| Euler's Method: Two Steps
[H] |
Recompute the slope at the new point before taking the second hop. |
| Euler's Method: A Nonlinear Field
[H] |
The recipe is unchanged when f(x, y) is nonlinear; just evaluate carefully. |
| Euler's Method: Over- or Under-Estimate
[H] |
Euler follows tangent lines, so concavity decides the direction of error. |
| Euler's Method: A Decimal Step
[H] |
A small decimal step works the same; convert to a fraction to stay exact. |