inline math

use single dollar signs for inline math:

rendered code
$E = mc^2$ $E = mc^2$
$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$
$e^{i\pi} + 1 = 0$ $e^{i\pi} + 1 = 0$

block equations

use double dollar signs for centered blocks:

$$
\sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{6}
$$

$$\sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{6}$$

$$
\int_{-\infty}^{\infty} e^{-x^2} dx = \sqrt{\pi}
$$

$$\int_{-\infty}^{\infty} e^{-x^2} dx = \sqrt{\pi}$$

fractions and roots

\frac{d}{dx} \left( \frac{u}{v} \right) = \frac{v \frac{du}{dx} - u \frac{dv}{dx}}{v^2}

$$\frac{d}{dx} \left( \frac{u}{v} \right) = \frac{v \frac{du}{dx} - u \frac{dv}{dx}}{v^2}$$

\sqrt[3]{x^3 + y^3} \neq x + y

$$\sqrt[3]{x^3 + y^3} \neq x + y$$

greek letters

rendered code rendered code
$\alpha$ \alpha $\Gamma$ \Gamma
$\beta$ \beta $\Delta$ \Delta
$\gamma$ \gamma $\Theta$ \Theta
$\delta$ \delta $\Lambda$ \Lambda
$\epsilon$ \epsilon $\Pi$ \Pi
$\theta$ \theta $\Sigma$ \Sigma
$\lambda$ \lambda $\Phi$ \Phi
$\mu$ \mu $\Omega$ \Omega
$\pi$ \pi
$\sigma$ \sigma
$\phi$ \phi
$\omega$ \omega

matrices

\begin{bmatrix} a & b \\ c & d \end{bmatrix}
\begin{bmatrix} x \\ y \end{bmatrix}
= \begin{bmatrix} ax + by \\ cx + dy \end{bmatrix}

$$\begin{bmatrix} a & b \\ c & d \end{bmatrix} \begin{bmatrix} x \\ y \end{bmatrix} = \begin{bmatrix} ax + by \\ cx + dy \end{bmatrix}$$

\det(A) = \begin{vmatrix} a & b \\ c & d \end{vmatrix} = ad - bc

$$\det(A) = \begin{vmatrix} a & b \\ c & d \end{vmatrix} = ad - bc$$

aligned equations

\begin{aligned}
(x + y)^2 &= (x + y)(x + y) \\
           &= x^2 + xy + yx + y^2 \\
           &= x^2 + 2xy + y^2
\end{aligned}

$$\begin{aligned} (x + y)^2 &= (x + y)(x + y) \\ &= x^2 + xy + yx + y^2 \\ &= x^2 + 2xy + y^2 \end{aligned}$$

calculus

\frac{d}{dx} \int_a^x f(t) \, dt = f(x)

$$\frac{d}{dx} \int_a^x f(t) , dt = f(x)$$

\lim_{x \to 0} \frac{\sin x}{x} = 1

$$\lim_{x \to 0} \frac{\sin x}{x} = 1$$

\nabla f = \frac{\partial f}{\partial x}\hat{i} + \frac{\partial f}{\partial y}\hat{j} + \frac{\partial f}{\partial z}\hat{k}

$$\nabla f = \frac{\partial f}{\partial x}\hat{i} + \frac{\partial f}{\partial y}\hat{j} + \frac{\partial f}{\partial z}\hat{k}$$

logic and sets

\forall x \in \mathbb{R}, \exists y \in \mathbb{R} : x + y = 0

$$\forall x \in \mathbb{R}, \exists y \in \mathbb{R} : x + y = 0$$

A \cup B = \{x : x \in A \lor x \in B\}

$$A \cup B = {x : x \in A \lor x \in B}$$

A \cap B \subseteq A \cup B

$$A \cap B \subseteq A \cup B$$

common symbols

rendered code rendered code
$\leq$ \leq $\partial$ \partial
$\geq$ \geq $\sum$ \sum
$\neq$ \neq $\prod$ \prod
$\approx$ \approx $\int$ \int
$\infty$ \infty $\rightarrow$ \rightarrow

notable formulas

gaussian distribution:

$$f(x) = \frac{1}{\sigma\sqrt{2\pi}} e^{-\frac{1}{2}\left(\frac{x-\mu}{\sigma}\right)^2}$$

bayes’ theorem:

$$P(A|B) = \frac{P(B|A) \cdot P(A)}{P(B)}$$

shannon entropy:

$$H(X) = -\sum_{i=1}^{n} p(x_i) \log_2 p(x_i)$$

fourier transform:

$$\hat{f}(\xi) = \int_{-\infty}^{\infty} f(x) e^{-2\pi i x \xi} , dx$$

euler’s identity:

$$e^{i\pi} + 1 = 0$$