ACT Preparation / Unit 7 ACT 0613 short lesson, about 20 seconds
Rational Exponents
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The idea
A rational exponent is a root: a^(1/n) is the nth root of a, and a^(m/n) is the nth root of a, raised to the m. The exponent rules still apply.
In practice
8^(2/3) = (∛8)² = 2² = 4; 16^(−1/2) = 1/4.
Where people slip
Take the root first: 27^(2/3) is (∛27)², or 9, without ever computing 27².
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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