Skill: Apply the power-of-a-power rule

Explanation and Free Practice Resources

A nested power such as (am)n(a^m)^n represents raising a quantity already formed by repeated multiplication to another whole-number power, so its equivalent form is amna^{mn}: the exponents are multiplied, not added. This reasoning applies to numerical bases, including powers of 10 used in scientific notation, and helps preserve the distinction from the product-of-powers rule; fractional exponents and more advanced generalizations are outside this scope.

Detailed Explanation: Apply the power-of-a-power rule

When a power is raised to another power, multiply the exponents:

(am)n=am⋅n(a^m)^n=a^{m\cdot n}

For example, simplify:

(103)2(10^3)^2
  1. The outside exponent, 22, means that 10310^3 is used as a factor twice:

(103)2=103⋅103 (10^3)^2=10^3\cdot10^3
  1. Because the bases are both 1010, use the product-of-powers rule to add the exponents:

103⋅103=103+3=106 10^3\cdot10^3=10^{3+3}=10^6
  1. Therefore:

(103)2=106 \boxed{(10^3)^2=10^6}

The exponents were multiplied because this was a power raised to a power:

3⋅2=63\cdot2=6

Do not add the exponents directly in (103)2(10^3)^2; adding is used when multiplying powers with the same base, such as 103⋅10210^3\cdot10^2.

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Exponents - Power Law with Variable Base (Positives, Exponent with Power to Exponent)


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