# Algebra Symbols

on . Posted in Nomenclature & Symbols for Engineering, Mathematics, and Science

## Algebra Symbols

This is a list of the most common Algebra symbols:

SymbolDefinitionExample
$$=$$ equal to $$5+4=9$$
$$\ne$$ not equal to $$5\ne4$$
$$\equiv$$ identical to $$a \equiv b$$
$$\not\equiv$$ not identical to $$a \not\equiv b$$
$$\sim$$ similar to $$a \sim b$$
$$\approx$$ approximately equal to $$a \approx b$$
$$>$$ greater than $$5>4$$
$$\gg$$ much greater than $$50000 \gg 4$$
$$<$$ less than $$4<5$$
$$\ll$$ much less than $$4 \ll 50000$$
$$\ge$$ greater than or equal to $$a \ge b$$
$$\le$$ less than or equal to $$a \le b$$
$$\Rightarrow$$ implies if...then $$a+b+c=1\;\Rightarrow\;c+b+a=1$$
$$\Leftrightarrow$$ is equivalent to if in only if (iff) $$a=b+1\;\Leftrightarrow\;b=a+1$$
$$\therefore$$ therefore $$a=b\; \therefore\; b=a$$
$$\sum$$ sigma, summation or sum of all $$\sum_{n=4}^8 n = 4+5+6+7+8=30$$
$$\left(\; \right)$$ parentheses, calculate expression inside first $$5\times \left(5+4\right) = 45$$
$$\left[\; \right]$$ brackets, calculate expression inside first $$\left[ \left(5+4\right) \times \left(9+4\right) \right] = 117$$
$$\{ \; \}$$ set, a collection $$A = \{4, 5, 9 \}$$
$$\lfloor x \rfloor$$ rounds number to lower integer $$\lfloor 5.4 \rfloor = 5$$
$$\lceil x \rceil$$ rounds number to upper integer $$\lceil 5.4 \rceil = 6$$
$$\left | x \right |$$ absolute value $$\left | -5 \right | = 5$$
$$\left \| x \right \|$$ normal
$$x!$$ factorial $$5!=5\;x\;4\;x\;3\;x\;2\;x\;1=120$$
$$a^n$$ power, an exponent $$5^4 = 3125$$
$$a\wedge b$$ caret, an exponent $$5\wedge4 = 3125$$
$$\sqrt a$$ Square root - $$\sqrt a \;\times\; \sqrt a = a$$ $$\sqrt 9= 3$$
$$^3\sqrt a$$ cube root - $$^3\sqrt a \;\times\; ^3\sqrt a \;\times\; ^3\sqrt a = a$$ $$^3\sqrt 9 = 2.08008382305$$
$$^4\sqrt a$$ 4th root - $$^4\sqrt a \;\times\; ^4\sqrt a \;\times\; ^4\sqrt a \;\times\; ^4\sqrt a = a$$ $$^4\sqrt 9 = 1.73205080757$$
$$^n\sqrt a$$ n-th root $$n=5\;$$, $$\;^n\sqrt 9 = 1.55184557391$$
$$\gamma$$ Euler-Mascheroni constant $$\gamma = 0.5772156649...$$
$$\Phi$$ golden ratio $$1 : 1.6180339887...$$
$$\pi$$ Pi,  $$\pi = 3.141592654...$$ $$C = \pi \cdot d = 2 \cdot \pi \cdot r$$