Which expression is correctly developed to use the power rule of exponents?

(7^4)^8
(-5)^0
(7^8)*(7^10)
12^9

1 answer

To identify which expression correctly uses the power rule of exponents, let's briefly review the power rule. The power rule states that \( (a^m)^n = a^{m \cdot n} \).

Now, let's evaluate each expression:

  1. \((7^4)^8\):

    • This can be expressed using the power rule: \[ (7^4)^8 = 7^{4 \cdot 8} = 7^{32} \]
    • This is a correct application of the power rule.
  2. \((-5)^0\):

    • Any non-zero number raised to the power of 0 is 1, which is not directly an application of the power rule but rather a property of exponents.
    • This doesn't utilize the power rule.
  3. \((7^8) \cdot (7^{10})\):

    • This can be combined using the property of exponents: \[ 7^8 \cdot 7^{10} = 7^{8+10} = 7^{18} \]
    • This expression makes use of the property of exponents but does not specifically utilize the power rule.
  4. \(12^9\):

    • This expression is simply in exponential form and does not employ any exponent rules.

Based on this analysis, the expression \((7^4)^8\) is the one that is correctly developed to use the power rule of exponents.