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Exponents & Radicals

Use the exponent rules and write radicals as fractional powers.

The rules

  • Same base: multiply means add exponents, divide means subtract, a power of a power means multiply.
  • a⁰ = 1 and a⁻ⁿ = 1/aⁿ.
  • √x = x^(1/2), and the nth root is x^(1/n).
  • Simplify radicals by pulling out perfect squares: √72 = 6√2.
Watch out: Adding exponents when you should multiply them in (x²)³ = x⁶.
Worked example

Simplify √72.

  1. 72 = 36 · 2.
  2. √36 = 6, so √72 = 6√2.

Answer: 6√2

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