Solve (12×7×9)^(-5): Negative Exponent Calculation

Question

Insert the corresponding expression:

(12×7×9)5= \left(12\times7\times9\right)^{-5}=

Video Solution

Solution Steps

00:00 Simplify the following problem
00:04 According to the laws of exponents, when we have a negative exponent
00:07 We can convert to the reciprocal number to obtain a positive exponent
00:11 We will apply this formula to our exercise
00:14 We'll write the reciprocal number (1 divided by the number)
00:17 Raise to the positive exponent
00:24 In order to expand parentheses of an exponent over multiplication
00:29 Raise each factor to the power
00:35 We will apply this formula to our exercise
00:42 This is the solution

Step-by-Step Solution

Start with (12×7×9)5 \left(12 \times 7 \times 9\right)^{-5} .

Apply the power of a product property, which states (xyz)n=xn×yn×zn (xyz)^n = x^n \times y^n \times z^n :
(12×7×9)5=125×75×95 \left(12 \times 7 \times 9\right)^{-5} = 12^{-5} \times 7^{-5} \times 9^{-5}

Use the negative exponent property, an=1an a^{-n} = \frac{1}{a^n} :
125×75×95=1125×175×195 12^{-5} \times 7^{-5} \times 9^{-5} = \frac{1}{12^{5}} \times \frac{1}{7^{5}} \times \frac{1}{9^{5}}

This results in:
1125×75×95 \frac{1}{12^5 \times 7^5 \times 9^5}

Thus, the solution to the expression is 1125×75×95 \frac{1}{12^5 \times 7^5 \times 9^5} .

Keep in mind - we could have used the rules in the other way around, first the negative exponent rule, and only then the product rule and the result would still be the same!

Answer

1125×75×95 \frac{1}{12^5\times7^5\times9^5}