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Can someone help me with this exponent problem?

Problem Solving — algebra and arithmetic (GMAT Focus Edition)
Expert replies
by acchi369 » Sun Sep 30, 2012 10:56 am
I am trying to simplify this problem:

[5^(a+b)^2] / [5^(a-b)^2

The first step I am taking is to apply the square to the (a+b) and (a-b) to get the following:

[5^(a^2 + 2ab + b^2)] / [5^(a^2 - 2ab + b^2)]

Simplifying that I thought it should be:

5^(a^4 + b^4)

however, the answer in the book says that it is: 5^(4ab)

How is that possible?
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Source: — Quantitative Reasoning |

by ImNOTaQUITTER » Sun Sep 30, 2012 5:24 pm
(5^x)/5^y = 5^(x-y)
Try again and you will get the answer.
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by acchi369 » Sun Sep 30, 2012 7:32 pm
Thanks. That is a simple rule that I should have picked up. I think I was confusing myself with the quadratic.
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by Jim@StratusPrep » Thu Oct 04, 2012 8:47 am
Your mistake was not subtracting properly after expanding the exponents.
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by rahultha » Sat Nov 03, 2012 11:05 am
Hello everyone.

This question is not difficult i will try to this.
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