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MathJax is super handy for expressing mathematical concepts in electrical engineering. What are the most common symbols and operators that you can use?

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    \$\begingroup\$ @Nick - Here's an old, related question used as MathJaX sandbox that has a number of good examples of MathJaX use in EE. Related but probably not a duplicate of this question. \$\endgroup\$ – Ricardo Jan 5 '16 at 16:07
  • \$\begingroup\$ @Nick et al. - Don't you guys think this question may be a bit too broad? It reminds me of the infamous, now 195 answers glossary question. \$\endgroup\$ – Ricardo Jan 5 '16 at 16:11
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    \$\begingroup\$ I hope this will help people up their game with MJ. There isn't a good all-in-one reference available for the most common stuff EEs do (I didn't bother with matrices for example but that info is out there) but this should help get someone from zero to pretty good in 20 minutes! \$\endgroup\$ – Daniel Jan 6 '16 at 18:24
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    \$\begingroup\$ MathJax is a subset of LaTeX mathmode symbols, there are already several decades worth of cheatsheets and sample documents online that you can peruse. One that I use often (skip tables 1-4) \$\endgroup\$ – crasic Jan 7 '16 at 5:09
  • \$\begingroup\$ While apparently not entirely applicable, the MathJax basic tutorial and quick reference on Mathematics Meta is a great ressource and almost always worth a visit. \$\endgroup\$ – Magic Smoke Jan 15 '16 at 18:38
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This is intended as a quick reference, where scrolling to the right section and pulling the symbol you want should not take more than a few seconds :)

This is specific to SE:EE, since a few things from Math don't seem to work here!

MathJax Enclosures:

Equation set: Put MathJax statements between double dollar signs:

The fake equation is: $$ A \times B = C $$

The fake equation is: $$ A \times B = C $$


Inline: Put MathJax between backslash dollar signs:

\$ \beta\$ is given in the datasheet as \$h_{FE} \$

\$ \beta\$ is given in the datasheet as \$h_{FE} \$

  • Note: Both kinds of enclosures can be used in both comments and titles!

Superscripts, Subscripts, and Grouping:

Use the caret symbol to designate superscripts and the underbar for subscripts:

\$x^2\$ is not equal to \$a_0\$

\$x^2\$ is not equal to \$a_0\$

Use curly braces {} to make operators work on groups of characters:

\$h_{FE}\$ is an unreliable parameter

\$h_{FE}\$ is an unreliable parameter

You can combine subscripts and superscripts for the same term:

 \$b_0^2\$ is the same as \$b^2_0\$

\$b_0^2\$ is the same as \$b^2_0\$ (order doesn't matter)

But be careful about grouping!

\$b_0^2\$ is not the same as \$b_{0^2}\$ or \$b^{2_0}\$

\$b_0^2\$ is not the same as \$b_{0^2}\$ or \$b^{2_0}\$


Fractions and Parentheses:

To create a fraction, you can use \frac or \over. \frac precedes two groups, and \over splits a group. Place \left( and \right) on either side of a group to get scaled parentheses. You can also use \left[...\right], \left\{...\right\}, \left|...\right|, or \left<...\right>.

$$\left( \frac{x+1}{y-5} \right)$$

$$\left( \frac{x+1}{y-5} \right)$$

$$\left| {x^2+1 \over y^2+1} \right|$$

$$\left| {x^2+1 \over y^2+1} \right|$$

And all in one gratuitous example:

$$\left\{ { \left<{x^2+1 \over y^2+1}\right> \over \left[ \frac{x+1}{y-5} \right] } \right\}$$

$$\left\{ { \left<{x^2+1 \over y^2+1}\right> \over \left[ \frac{x+1}{y-5} \right] } \right\}$$


Greek Letters:

(for small uses, HTML character codes are also available and can optionally be italicized)

  • \$\alpha\$ \alphaα &alpha;)
  • \$\beta\$ \betaβ &beta;)
  • \$\gamma\$ \gammaγ &gamma;)
  • \$ \Gamma\$ \GammaΓ &Gamma;)
  • \$\delta\$ \deltaδ &delta;)
  • \$\Delta\$ \DeltaΔ &Delta;)
  • \$\epsilon\$ \epsilonε &epsilon;)
  • \$\varepsilon\$ \varepsilon
  • \$\zeta\$ \zetaζ &zeta;)
  • \$\eta\$ \etaη &eta;)
  • \$\theta\$ \thetaθ &theta;)
  • \$\vartheta\$ \vartheta
  • \$\Theta\$ \ThetaΘ &Theta;)
  • \$\iota\$ \iota
  • \$\kappa\$ \kappa
  • \$\varkappa\$ \varkappa
  • \$\lambda\$ \lambda
  • \$\Lambda\$ \Lambda
  • \$\mu\$ \mu
  • \$\nu\$ \nu
  • \$\xi\$ \xi
  • \$\Xi\$ \Xi
  • \$\omicron\$ \omicron
  • \$\pi\$ \pi
  • \$\varpi\$ \varpi
  • \$\Pi\$ \Pi
  • \$\rho\$ \rho
  • \$\varrho\$ \varrho
  • \$\sigma\$ \sigma
  • \$\varsigma\$ \varsigma
  • \$\Sigma\$ \Sigma
  • \$\tau\$ \tau
  • \$\upsilon\$ \upsilon
  • \$\Upsilon\$ \Upsilon
  • \$\phi\$ \phi
  • \$\varphi\$ \varphi
  • \$\Phi\$ \Phi
  • \$\chi\$ \chi
  • \$\psi\$ \psi
  • \$\Psi\$ \Psi
  • \$\omega\$ \omega
  • \$\Omega\$ \Omega

Equality:

  • \$\lt\$ \lt
  • \$\gt\$ \gt
  • \$\le\$ \le
  • \$\ge\$ \ge
  • \$\neq\$ \neq
  • \$\approx\$ \approx
  • \$\not\approx\$ \not\approx

Operators:

  • \$\times\$ \times
  • \$\div\$ \div
  • \$\cdot\$ \cdot
  • \$\oplus\$ \oplus (xor)
  • \$\nabla\$ \nabla ("del operator")
  • \$\partial\$ \partial

Miscellaneous:

  • \$\to\$ \to
  • \$\Im\$ \Im (imaginary part)
  • \$\Re\$ \Re (real part)
  • \$\infty\$ \infty
  • \$\pm\$ \$\mp\$ \pm \mp
  • \$a_0,\ldots,a_x\$ a_0,\ldots,a_x (lower ellipses)
  • \$a_0 + \cdots +a_{x-1}+a_x\$ a_0 + \cdots +a_{x-1}+a_x (mid ellipses)

Special Functions

  • \$\sin(x)\$ \sin(x)
  • \$\cos(x)\$ \cos(x)
  • \$\tan(x)\$ \tan(x)
  • \$\tan^{-1}({a\over b})\$ \tan^{-1}({a\over b})
  • \$\sqrt{x^2 \over y^2}\$ \sqrt{x^2 \over y^2}
  • \$\sqrt[x]{a+b}\$ \sqrt[x]{a+b}
  • \$\max\{a,b\}\$ \max\{a,b\}
  • \$\min\{a,b\}\$ \min\{a,b\}
  • \$\ln(x)\$ \ln(x)
  • \$\log_{10}(x)\$ \log_{10}(x)

Space:

Narrow: \, $$a\,b$$ Single: \; $$a\;b$$ Quad: \quad $$a \quad b$$ Quad quad: \qquad $$a\qquad b$$


Vector Notation:

Each style of vector notation has a single character and a multi-character delineation, but the multi-character version is also usable in the single-character case.

Hats, unit vectors:

$$\hat a \quad \widehat{abc}$$

$$\hat a \quad \widehat{abc}$$

Magnitudes, lines:

$$\bar a \quad \overline{abc}$$

$$\bar a \quad \overline{abc}$$

Vectors:

$$\vec a \quad \overrightarrow{ac}$$

$$\vec a \quad \overrightarrow{ac}$$


Limits, Integrals, Sums, and Products:

These functions display differently depending on whether they are inline with \$...\$ or set apart with $$...$$.

With inline text, limits will be rendered inline as default:

Inline: \$\lim_{x\to 0}x\$

Inline: \$\lim_{x\to 0}x\$

In an equation, limits will be rendered more traditionally by default:

$$\lim_{x\to 0}x$$

$$\lim_{x\to 0}x$$

In order to get the more traditional rendering using inline MathJax, you must use the \limits operator:

Some inline text oh look a limit! \$\lim \limits_{x\to 0}x\$

Some inline text oh look a limit! \$\lim \limits_{x\to 0}x\$

The \limits operator should work similarly for all symbols in this section.

$$\int_{a}^{b}x\;dx$$

$$\int_{a}^{b}x\;dx$$

$$\iint_V xy\;dx\;dy$$

$$\iint_V xy\;dx\;dy$$

$$\iiint_V xyz\;dx\;dy\;dz$$

$$\iiint_V xyz\;dx\;dy\;dz$$

$$\oint_V f(s)\;ds$$

$$\oint_V f(s)\;ds$$

$$\sum_{n=1}^{\infty} 2^{n-1}=1$$

$$\sum_{n=1}^{\infty} 2^{n-1}=1$$

$$\prod_{i=a}^{b} f(i)$$

$$\prod_{i=a}^{b} f(i)$$

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    \$\begingroup\$ Thank you for writing this. It's more helpful than the global SE references. \$\endgroup\$ – Adam Haun Jan 7 '16 at 19:47
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One handy thing I've picked up is a quick degree symbol: writing

360\$^\circ\$

gives you

360\$^\circ\$

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    \$\begingroup\$ quick comparison between regular degree symbol from keyboard ° and the mathjax circle \circ next to each other: 360\$°^\circ\$ 360\$°^\circ\$ \$\endgroup\$ – Magic Smoke Jan 15 '16 at 19:17

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