Change
Part III: Moving — Chapters 8, 9, 10 — Plane Position: (0, -0.2) radius 0.4 — 58 Primitives
Workflow
- Verify continuity at the point or interval of interest — confirm the function meets the three conditions (defined, limit exists, limit equals value)
- Compute derivatives using the appropriate rule (power, chain, product, quotient) to find rates of change
- Find critical points where f'(x) = 0 or f'(x) is undefined, then classify using the first or second derivative test
- Integrate using antiderivatives and the Fundamental Theorem of Calculus to accumulate quantities
- Solve ODEs by identifying the equation type and applying the matching technique (separation, integrating factor, etc.)
Key Concepts
Derivative (definition): The derivative of f at x is f'(x) = lim_{h->0} [f(x+h) - f(x)]/h, when this limit exists. It represents the instantaneous rate of change of f at x, and the slope of the tangent line to the graph at (x, f(x)).
- computing the instantaneous rate of change of a quantity
- finding the slope of a curve at a specific point
Definite Integral (definition): The definite integral of f from a to b is integral_a^b f(x)dx = lim_{n->inf} sum_{i=1}^{n} f(x_i*)*Delta_x, when this limit exists. It represents the signed area between f and the x-axis over [a,b].
- computing the total accumulation of a quantity over an interval
- finding the area enclosed between a curve and the x-axis
Ordinary Differential Equation (definition): An ordinary differential equation (ODE) is an equation involving a function y(x) and its derivatives: F(x, y, y', y'', ..., y^(n)) = 0. The order is the highest derivative present. A solution is a function that satisfies the equation on an interval.
- modeling systems where the rate of change depends on the current state
- describing physical laws relating a quantity to its derivatives
Limit (definition): The limit of f(x) as x approaches a is L, written lim_{x->a} f(x) = L, if for every epsilon > 0 there exists delta > 0 such that 0 < |x - a| < delta implies |f(x) - L| < epsilon.
- finding the value a function approaches near a point where it may not be defined
- establishing the foundation for derivatives and integrals
Continuity (definition): A function f is continuous at a point a if: (1) f(a) is defined, (2) lim_{x->a} f(x) exists, and (3) lim_{x->a} f(x) = f(a). f is continuous on an interval if continuous at every point in the interval.
- verifying that a function has no jumps or breaks at a point
- determining the domain on which a function is well-behaved for calculus
Higher-Order Derivatives (definition): The nth derivative f^(n)(x) is obtained by differentiating f n times. f''(x) = d^2f/dx^2 (acceleration, concavity). f^(n)(x) = d^n f/dx^n. A function is C^n if its first n derivatives are continuous.
- computing acceleration as the second derivative of position
- determining concavity and inflection points of curves
Critical Point (definition): A critical point of f is a value c in the domain of f where f'(c) = 0 or f'(c) does not exist. Critical points are candidates for local maxima, local minima, or inflection points.
- finding where a function might achieve its maximum or minimum value
- locating turning points of a curve
Antiderivative (Indefinite Integral) (definition): An antiderivative of f is a function F such that F'(x) = f(x). The indefinite integral integral f(x)dx = F(x) + C represents the family of all antiderivatives, where C is an arbitrary constant.
- finding a function whose derivative is a given function
- reversing differentiation to recover original functions
Power Rule (theorem): For any real number n: d/dx(x^n) = n*x^(n-1). This holds for integer, rational, and real exponents (where the function is defined).
- differentiating polynomial terms and power functions
- finding the derivative of any expression of the form x^n
Chain Rule (theorem): If g is differentiable at x and f is differentiable at g(x), then the composite function f(g(x)) is differentiable at x with: d/dx[f(g(x))] = f'(g(x)) * g'(x).
- differentiating compositions of functions like sin(x^2) or e^(3x)
- computing rates of change through connected relationships
Composition Patterns
- Limit + perception-real-line-completeness -> Foundation for epsilon-delta analysis: the limit exists because R is complete (nested)
- Continuity + change-limit -> The no-surprises condition: the limit equals the function value (sequential)
- Derivative + change-fundamental-theorem-2 -> The fundamental connection: differentiation and integration are inverse operations (parallel)
- Differentiability + change-continuity -> Hierarchy: differentiable => continuous => defined (each implication is strict) (sequential)
- Higher-Order Derivatives + change-taylor-series -> Taylor coefficients: f(x) ~ sum f^(n)(a)/n! * (x-a)^n, each coefficient from an nth derivative (sequential)
- Critical Point + change-first-derivative-test -> Complete local extremum classification: find critical points then test sign changes (sequential)
- Inflection Point + change-critical-point -> Complete curve analysis: critical points for extrema, inflection points for concavity changes (parallel)
- Power Rule + change-chain-rule -> Generalized power rule: d/dx(f(x)^n) = n*f(x)^(n-1)*f'(x) (nested)
- Chain Rule + change-power-rule -> d/dx[f(x)]^n = n[f(x)]^(n-1) * f'(x) (nested)
- Product Rule + change-quotient-rule -> Complete toolkit for differentiating rational expressions (parallel)
Cross-Domain Links
- perception: Compatible domain for composition and cross-referencing
- waves: Compatible domain for composition and cross-referencing
- structure: Compatible domain for composition and cross-referencing
- emergence: Compatible domain for composition and cross-referencing
- synthesis: Compatible domain for composition and cross-referencing
Activation Patterns
- derivative
- integral
- rate
- differential
- Taylor
- optimization
- limit
- continuous
- accumulation