0

I'm not entirely sure whether this is a suitable problem to ask. However, in trying to solve an index problem, I have been getting stuck in the same place for a while.

The question is:

$$(9a^3 b^{-4})^{1/2} \times 2(a^{1/2}b^{−2})^{−2}$$

I know that the answer is
$$6a^{1/2} \times b^{2}$$

But I'm unsure exactly how to get there. I know I must start by expanding; however, I then get stuck.

S.Ban
  • 41

3 Answers3

2

Try using these two basic principles:

$(a^x)^y = a^{x \cdot y}$

$a^x \cdot a^y = a^{x+y}$

Bram28
  • 100,612
  • 6
  • 70
  • 118
1

You have $$(9a^3 b^{-4})^{1/2} \times 2(a^{1/2}b^{−2})^{−2} = 9^{1/2}a^{3/2}b^{-2} \times 2a^{-1}b^{4} = \frac{3a^{3/2}}{b^{2}} \times \frac{2b^4}{a} = 6a^{1/2}b^2$$

mate89
  • 538
  • Oh right thanks, I had expanded my equasion but found myself stuck for the next step, that makes a lot of sense. Thank you – S.Ban Sep 24 '17 at 00:36
0

The answer to your question can be viewed via this link: https://i.stack.imgur.com/EKBDO.jpg