Question: x with Powers of a, b and c

Comment on x with Powers of a, b and c

for x^3a and using the law, how we figured out that it will become (x^a)^3 and not (x^3)^a?
gmat-admin's picture

It's true that x^(3a) = (x^a)^3 = (x^3)^a
So, we COULD have rewritten x^(3a) as (x^3)^a
However, doing so would not have helped us answer the question. We're not given any information about the value of x^3, so our solution would become stalled.

However, we ARE given information about the value of x^a.
So, if we rewrite x^(3a) as (x^a)^3, we can use the fact that x^a = 2 to help us solve the question.

Does that help?

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