Catalog / Calculus Cheatsheet
Calculus Cheatsheet
A comprehensive calculus cheat sheet covering essential concepts, formulas, and techniques. This cheat sheet is designed to serve as a quick reference guide for students and professionals alike, providing a concise overview of calculus principles and methods.
Limits and Continuity
Limit Definitions
Formal Definition: |
For every ε > 0, there exists a δ > 0 such that if 0 < |x - a| < δ, then |f(x) - L| < ε. |
Intuitive Definition: |
As x approaches a, f(x) approaches L. |
One-Sided Limits: |
\lim_{x \to a^-} f(x) and \lim_{x \to a^+} f(x) |
Limit Laws
\lim_{x \to a} [f(x) + g(x)] = \lim_{x \to a} f(x) + \lim_{x \to a} g(x) |
\lim_{x \to a} [cf(x)] = c \lim_{x \to a} f(x) |
\lim_{x \to a} [f(x)g(x)] = \lim_{x \to a} f(x) \cdot \lim_{x \to a} g(x) |
\lim_{x \to a} \frac{f(x)}{g(x)} = \frac{\lim_{x \to a} f(x)}{\lim_{x \to a} g(x)}, if \lim_{x \to a} g(x) \neq 0 |
Continuity
Definition: |
A function f(x) is continuous at x = a if \lim_{x \to a} f(x) = f(a). This means that f(a) exists, the limit exists, and they are equal. |
Types of Discontinuities: |
Removable, Jump, Infinite |
Derivatives
Basic Differentiation Rules
Power Rule: |
\frac{d}{dx}(x^n) = nx^{n-1} |
Constant Rule: |
\frac{d}{dx}(c) = 0 |
Constant Multiple Rule: |
\frac{d}{dx}(cf(x)) = c \frac{d}{dx}(f(x)) |
Sum/Difference Rule: |
\frac{d}{dx}(f(x) \pm g(x)) = \frac{d}{dx}(f(x)) \pm \frac{d}{dx}(g(x)) |
Product and Quotient Rules
Product Rule: |
\frac{d}{dx}[f(x)g(x)] = f'(x)g(x) + f(x)g'(x) |
Quotient Rule: |
\frac{d}{dx} \left[ \frac{f(x)}{g(x)} \right] = \frac{f'(x)g(x) - f(x)g'(x)}{[g(x)]^2} |
Chain Rule
Chain Rule: |
\frac{d}{dx}[f(g(x))] = f'(g(x)) \cdot g'(x) |
Derivatives of Trig Functions
\frac{d}{dx}(\sin x) |
\cos x |
\frac{d}{dx}(\cos x) |
-\sin x |
\frac{d}{dx}(\tan x) |
\sec^2 x |
\frac{d}{dx}(\csc x) |
-\csc x \cot x |
\frac{d}{dx}(\sec x) |
\sec x \tan x |
\frac{d}{dx}(\cot x) |
-\csc^2 x |
Integrals
Basic Integration Rules
Power Rule: |
\int x^n dx = \frac{x^{n+1}}{n+1} + C, for n \neq -1 |
Constant Rule: |
\int c dx = cx + C |
Constant Multiple Rule: |
\int cf(x) dx = c \int f(x) dx |
Sum/Difference Rule: |
\int [f(x) \pm g(x)] dx = \int f(x) dx \pm \int g(x) dx |
\int \frac{1}{x} dx |
ln|x| + C |
\int e^x dx |
e^x + C |
Integration by Parts
Formula: |
\int u dv = uv - \int v du |
Trigonometric Integrals
\int \sin x dx |
-\cos x + C |
\int \cos x dx |
\sin x + C |
\int \sec^2 x dx |
\tan x + C |
\int \csc^2 x dx |
-\cot x + C |
\int \sec x \tan x dx |
\sec x + C |
\int \csc x \cot x dx |
-\csc x + C |
Trigonometric Substitution
Use when you have integrals involving \sqrt{a^2 - x^2}, \sqrt{a^2 + x^2}, or \sqrt{x^2 - a^2}. Substitute x = a\sin \theta, x = a\tan \theta, or x = a\sec \theta respectively. |
Applications of Derivatives
Related Rates
Identify the variables, find the equation relating them, differentiate with respect to time, and solve for the desired rate. |
Optimization
Find critical points by setting the first derivative to zero or undefined, then use the first or second derivative test to determine local maxima and minima. Check endpoints for absolute extrema. |
L'Hôpital's Rule
When to Use: |
For limits of the form \frac{0}{0} or \frac{\infty}{\infty}. |
Rule: |
\lim_{x \to a} \frac{f(x)}{g(x)} = \lim_{x \to a} \frac{f'(x)}{g'(x)} |
Mean Value Theorem
Theorem: |
If f is continuous on [a, b] and differentiable on (a, b), then there exists a c in (a, b) such that f'(c) = \frac{f(b) - f(a)}{b - a} |