Mathematical Formulas

A collection of mathematical formulas organized by category.

Algebra

Basic algebraic formulas and identities

Quadratic Formula

x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}

Difference of Squares

a2b2=(a+b)(ab)a^2 - b^2 = (a+b)(a-b)

Square of Binomial

(a+b)2=a2+2ab+b2(a+b)^2 = a^2 + 2ab + b^2

Cube of Binomial

(a+b)3=a3+3a2b+3ab2+b3(a+b)^3 = a^3 + 3a^2b + 3ab^2 + b^3

Sum of Cubes

a3+b3=(a+b)(a2ab+b2)a^3 + b^3 = (a+b)(a^2-ab+b^2)

Difference of Cubes

a3b3=(ab)(a2+ab+b2)a^3 - b^3 = (a-b)(a^2+ab+b^2)

Calculus

Differentiation, integration, and related concepts

Power Rule (Differentiation)

ddx[xn]=nxn1\frac{d}{dx}[x^n] = nx^{n-1}

Product Rule

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

Quotient Rule

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

Chain Rule

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

Power Rule (Integration)

xndx=xn+1n+1+C,n1\int x^n dx = \frac{x^{n+1}}{n+1} + C, \quad n \neq -1

Exponential Integration

exdx=ex+C\int e^x dx = e^x + C

Logarithmic Integration

1xdx=lnx+C\int \frac{1}{x} dx = \ln|x| + C

Geometry

Formulas for areas, volumes, and properties of shapes

Circle Area

A=πr2A = \pi r^2

Circle Circumference

C=2πrC = 2\pi r

Sphere Volume

V=43πr3V = \frac{4}{3}\pi r^3

Sphere Surface Area

A=4πr2A = 4\pi r^2

Cylinder Volume

V=πr2hV = \pi r^2 h

Cone Volume

V=13πr2hV = \frac{1}{3}\pi r^2 h

Pythagorean Theorem

a2+b2=c2a^2 + b^2 = c^2

Trigonometry

Trigonometric identities and formulas

Sine and Cosine Relation

sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1

Tangent Definition

tanθ=sinθcosθ\tan \theta = \frac{\sin \theta}{\cos \theta}

Sine Addition

sin(α+β)=sinαcosβ+cosαsinβ\sin(\alpha + \beta) = \sin \alpha \cos \beta + \cos \alpha \sin \beta

Cosine Addition

cos(α+β)=cosαcosβsinαsinβ\cos(\alpha + \beta) = \cos \alpha \cos \beta - \sin \alpha \sin \beta

Double Angle (Sine)

sin2θ=2sinθcosθ\sin 2\theta = 2\sin \theta \cos \theta

Double Angle (Cosine)

cos2θ=cos2θsin2θ=2cos2θ1=12sin2θ\cos 2\theta = \cos^2 \theta - \sin^2 \theta = 2\cos^2 \theta - 1 = 1 - 2\sin^2 \theta

Law of Sines

asinA=bsinB=csinC\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}

Law of Cosines

c2=a2+b22abcosCc^2 = a^2 + b^2 - 2ab\cos C

Statistics & Probability

Statistical formulas and probability concepts

Arithmetic Mean

xˉ=1ni=1nxi\bar{x} = \frac{1}{n}\sum_{i=1}^{n} x_i

Variance

σ2=1ni=1n(xixˉ)2\sigma^2 = \frac{1}{n}\sum_{i=1}^{n} (x_i - \bar{x})^2

Standard Deviation

σ=1ni=1n(xixˉ)2\sigma = \sqrt{\frac{1}{n}\sum_{i=1}^{n} (x_i - \bar{x})^2}

Normal Distribution

f(x)=1σ2πe12(xμσ)2f(x) = \frac{1}{\sigma\sqrt{2\pi}}e^{-\frac{1}{2}(\frac{x-\mu}{\sigma})^2}

Binomial Coefficient

(nk)=n!k!(nk)!\binom{n}{k} = \frac{n!}{k!(n-k)!}

Bayes' Theorem

P(AB)=P(BA)P(A)P(B)P(A|B) = \frac{P(B|A)P(A)}{P(B)}

Correlation Coefficient

r=i=1n(xixˉ)(yiyˉ)i=1n(xixˉ)2i=1n(yiyˉ)2r = \frac{\sum_{i=1}^{n} (x_i - \bar{x})(y_i - \bar{y})}{\sqrt{\sum_{i=1}^{n} (x_i - \bar{x})^2 \sum_{i=1}^{n} (y_i - \bar{y})^2}}

Linear Algebra

Matrices, determinants, and vector operations

Matrix Multiplication

Cij=k=1nAikBkjC_{ij} = \sum_{k=1}^{n} A_{ik}B_{kj}

2×2 Determinant

det(abcd)=adbc\det\begin{pmatrix} a & b \\ c & d \end{pmatrix} = ad - bc

Dot Product

ab=i=1naibi=abcosθ\vec{a} \cdot \vec{b} = \sum_{i=1}^{n} a_i b_i = |\vec{a}||\vec{b}|\cos\theta

Cross Product (3D)

a×b=(a2b3a3b2,a3b1a1b3,a1b2a2b1)\vec{a} \times \vec{b} = (a_2b_3 - a_3b_2, a_3b_1 - a_1b_3, a_1b_2 - a_2b_1)

Eigenvalue Equation

Av=λvA\vec{v} = \lambda\vec{v}

Matrix Trace

tr(A)=i=1nAii\text{tr}(A) = \sum_{i=1}^{n} A_{ii}

All Converters