Math Exponents and roots Special exponent laws

Special exponent laws

In addition to the actual exponent laws, there are a few more special cases.

  1. Negative base

    if $x$ is straight: $(-a)^x=a^x$
    if $x$ is odd: $(-a)^x=-(a^x)$
  2. Negative exponents

    $a^{-x}=\frac{1}{a^x}$
  3. Fractions in exponents

    $a^{\frac{m}{n}}=\sqrt[n]{a^m}$

Examples

  • $(-5)^2=5^2=25$
    $(-2)^3=-(2^3)=-8$

  • $6^{-2}=\frac{1}{6^2}$ $=\frac{1}{36}$

  • $2^\frac43=\sqrt[3]{2^4}$