# Miscellaneous Symbols

Written by Jerry Ratzlaff on . Posted in Nomenclature & Symbols for Engineering, Mathematics, and Science

## Miscellaneous Symbols

This is a list of the most common miscellaneous symbols:

Symbol  Symbol  DefinitionExample
$$a^n$$ - power, an exponent $$5^4 = 3125$$
% - percent, $$1$$% $$= 1/100$$ $$5$$% $$\times 4 = 0.2$$
$$\Phi$$ Phi golden ratio $$1 : 1.6180339887...$$
$$\pi$$ pi Pi $$\pi = 3.141592654...$$
$$e$$ - Euler's number constant $$e = 2.718281828...$$
$$\gamma$$ gamma Euler-Mascheroni constant $$\gamma = 0.5772156649...$$
$$x!$$ - fractional $$5!=5\;x\;4\;x\;3\;x\;2\;x\;1=120$$
$$\int$$ int integral, adding slices to find the whole $$\int 2x \; dx$$
$$\sum$$ sum sigma, summation or sum of all $$\sum_{n=4}^8 n = 4+5+6+7+8=30$$
$$\exists$$ exists there exists
$$\nexists$$ nexists there does not exists
$$\forall$$ forall for all
$$\infty$$ infty infinity
$$\propto$$ propto porportional to $$\frac{1}{4} \propto \frac{2}{8}$$
$$i$$ - imaginary number $$i=\sqrt{-1}$$