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2 votes
I need help on doing (2a^-6 b^4)^3 • 2a^-3 b^-5?

User Gamlor
by
5.6k points

1 Answer

3 votes

Steps

So here are a few rules with exponents that we will be applying for this problem:

  • Powering a power:
    (x^m)^n=x^(m*n)
  • Multiplying powers with the same base:
    x^m*x^n=x^(m+n)
  • Converting negative exponents to positive exponents:
    x^(-m)=(1)/(m^n)\ \textsf{//}\ (1)/(x^(-m))=x^m

Firstly, solve the outermost power:


(2a^(-6) b^4)^3*2a^(-3) b^(-5)\\2^3a^(-6*3) b^(4*3)*2a^(-3) b^(-5)\\8a^(-18)b^(12)*2a^(-3)b^(-5)

Next, multiply:


8a^(-18)b^(12)*2a^(-3)b^(-5)\\8*2a^(-18+(-3))b^(12+(-5))\\16a^(-21)b^7

Finally, convert the negative exponents:


16a^(-21)b^7\\\\(16b^7)/(a^(21))

Answer

In short, your final answer is
(16b^7)/(a^(21))

User Lennaert
by
5.7k points
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