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Exponent Rules — All Laws of Exponents Reference

A complete reference of exponent rules — every law of exponents you need for algebra and pre-calculus. Includes rules for products, quotients, powers, zero, negative, and fractional exponents, plus their radical equivalents.

Core Exponent Rules

Product of Powers
aman=am+na^m \cdot a^n = a^{m+n}
Quotient of Powers
aman=amn(a0)\frac{a^m}{a^n} = a^{m-n} \quad(a \ne 0)
Power of a Power
(am)n=amn(a^m)^n = a^{m n}
Power of a Product
(ab)n=anbn(ab)^n = a^n b^n
Power of a Quotient
(ab)n=anbn(b0)\left(\frac{a}{b}\right)^n = \frac{a^n}{b^n} \quad(b \ne 0)

Zero, Negative & One Exponents

Zero Exponent
a0=1(a0)a^0 = 1 \quad(a \ne 0)
One Exponent
a1=aa^1 = a
Negative Exponent
an=1an(a0)a^{-n} = \frac{1}{a^n} \quad(a \ne 0)
Negative Exponent (Reciprocal)
(ab)n=(ba)n\left(\frac{a}{b}\right)^{-n} = \left(\frac{b}{a}\right)^n

Fractional Exponents & Radicals

Unit Fractional
a1/n=ana^{1/n} = \sqrt[n]{a}
General Fractional
am/n=amn=(an)ma^{m/n} = \sqrt[n]{a^m} = (\sqrt[n]{a})^m
Square Root as Exponent
a=a1/2\sqrt{a} = a^{1/2}
Cube Root as Exponent
a3=a1/3\sqrt[3]{a} = a^{1/3}
Negative Fractional
am/n=1amna^{-m/n} = \frac{1}{\sqrt[n]{a^m}}

Special Bases

Powers of 10
10n=1000n zeros10^n = \underbrace{100\cdots0}_{n\text{ zeros}}
Scientific Notation
a×10n(1a<10)a \times 10^n \quad(1 \le |a| < 10)
Powers of e (definition)
ex=limn(1+xn)ne^x = \lim_{n \to \infty}\left(1 + \tfrac{x}{n}\right)^n
Powers of e (series)
ex=k=0xkk!e^x = \sum_{k=0}^{\infty} \frac{x^k}{k!}

Solving Exponential Equations

Same Base
ax=ay    x=y(a>0, a1)a^x = a^y \iff x = y \quad(a > 0,\ a \ne 1)
Take the Log (any base)
ax=b    x=logaba^x = b \iff x = \log_a b
Change of Base
ax=b    x=lnblnaa^x = b \iff x = \frac{\ln b}{\ln a}
A=PertA = P e^{rt}
Compound Interest
A=P(1+rn)ntA = P\left(1 + \tfrac{r}{n}\right)^{n t}

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