Calculus I Formula Reference Card

Essential formulas for Calculus I — derivatives, integrals, limits, and theorems.

Limit Laws

Given \(\lim_{x \to a} f(x) = L\) and \(\lim_{x \to a} g(x) = M\):

Law Formula

Sum/Difference

\(\lim_{x \to a} [f(x) \pm g(x)] = L \pm M\)

Constant Multiple

\(\lim_{x \to a} [c \cdot f(x)] = c \cdot L\)

Product

\(\lim_{x \to a} [f(x) \cdot g(x)] = L \cdot M\)

Quotient

\(\lim_{x \to a} \frac{f(x)}{g(x)} = \frac{L}{M}, \quad M \neq 0\)

Power

\(\lim_{x \to a} [f(x)]^n = L^n\)

Squeeze Theorem

If \(g(x) \leq f(x) \leq h(x)\) and \(\lim g = \lim h = L\), then \(\lim f = L\)

Special Limits

  • \(\lim_{x \to 0} \frac{\sin x}{x} = 1\)

  • \(\lim_{x \to 0} \frac{1 - \cos x}{x} = 0\)

  • \(\lim_{x \to \infty} \left(1 + \frac{1}{x}\right)^x = e\)

  • \(\lim_{x \to 0} \frac{e^x - 1}{x} = 1\)

Derivative Rules

Basic Rules

Rule Formula

Constant

\(\frac{d}{dx}[c] = 0\)

Power Rule

\(\frac{d}{dx}[x^n] = n x^{n-1}\)

Constant Multiple

\(\frac{d}{dx}[c \cdot f(x)] = c \cdot f'(x)\)

Sum/Difference

\(\frac{d}{dx}[f \pm g] = f' \pm g'\)

Product Rule

\(\frac{d}{dx}[f \cdot g] = f' g + f g'\)

Quotient Rule

\(\frac{d}{dx}\left[\frac{f}{g}\right] = \frac{f' g - f g'}{g^2}\)

Chain Rule

\(\frac{d}{dx}[f(g(x))] = f'(g(x)) \cdot g'(x)\)

Trigonometric Derivatives

Function Derivative

\(\sin x\)

\(\cos x\)

\(\cos x\)

\(-\sin x\)

\(\tan x\)

\(\sec^2 x\)

\(\cot x\)

\(-\csc^2 x\)

\(\sec x\)

\(\sec x \tan x\)

\(\csc x\)

\(-\csc x \cot x\)

Inverse Trigonometric Derivatives

Function Derivative

\(\arcsin x\)

\(\frac{1}{\sqrt{1 - x^2}}\)

\(\arccos x\)

\(-\frac{1}{\sqrt{1 - x^2}}\)

\(\arctan x\)

\(\frac{1}{1 + x^2}\)

Exponential and Logarithmic Derivatives

Function Derivative

\(e^x\)

\(e^x\)

\(a^x\)

\(a^x \ln a\)

\(\ln x\)

\(\frac{1}{x}\)

\(\log_a x\)

\(\frac{1}{x \ln a}\)

Integration Formulas

Basic Integrals

Integral Result

\(\int x^n \, dx\)

\(\frac{x^{n+1}}{n+1} + C, \quad n \neq -1\)

\(\int \frac{1}{x} \, dx\)

latexmath:[\ln

x

+ C]

\(\int e^x \, dx\)

\(e^x + C\)

\(\int a^x \, dx\)

\(\frac{a^x}{\ln a} + C\)

Trigonometric Integrals

Integral Result

\(\int \sin x \, dx\)

\(-\cos x + C\)

\(\int \cos x \, dx\)

\(\sin x + C\)

\(\int \sec^2 x \, dx\)

\(\tan x + C\)

\(\int \csc^2 x \, dx\)

\(-\cot x + C\)

\(\int \sec x \tan x \, dx\)

\(\sec x + C\)

\(\int \csc x \cot x \, dx\)

\(-\csc x + C\)

Integrals Producing Inverse Trig

Integral Result

\(\int \frac{1}{\sqrt{1-x^2}} \, dx\)

\(\arcsin x + C\)

\(\int \frac{1}{1+x^2} \, dx\)

\(\arctan x + C\)

\(\int \frac{1}{x\sqrt{x^2-1}} \, dx\)

\(\operatorname{arcsec} \lvert x \rvert + C\)

Key Theorems

Intermediate Value Theorem (IVT)

If \(f\) is continuous on \(\lbrack a, b \rbrack\) and \(N\) is between \(f(a)\) and \(f(b)\), then there exists \(c \in (a, b)\) such that \(f(c) = N\).

Extreme Value Theorem (EVT)

If \(f\) is continuous on \(\lbrack a, b \rbrack\), then \(f\) attains an absolute maximum and minimum on \(\lbrack a, b \rbrack\).

Mean Value Theorem (MVT)

If \(f\) is continuous on \(\lbrack a, b \rbrack\) and differentiable on \((a, b)\), then there exists \(c \in (a, b)\) such that:

\[f'(c) = \frac{f(b) - f(a)}{b - a}\]

Rolle’s Theorem

Special case of MVT: if \(f(a) = f(b)\), then there exists \(c \in (a, b)\) such that \(f'(c) = 0\).

Fundamental Theorem of Calculus

Part 1: If \(f\) is continuous on \(\lbrack a, b \rbrack\), then \(F(x) = \int_a^x f(t) \, dt\) is differentiable and:

\[F'(x) = f(x)\]

Part 2: If \(f\) is continuous on \(\lbrack a, b \rbrack\) and \(F\) is any antiderivative of \(f\), then:

\[\int_a^b f(x) \, dx = F(b) - F(a)\]

Net Change Theorem

\[\int_a^b F'(x) \, dx = F(b) - F(a)\]

The integral of a rate of change gives the net change.