Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a literal equation that needs to be solved for: $$r_{a}$$

Here is the equation:

$$ \frac{ T_{a} }{ T_{b} } = \left( \frac{ r_{a} }{ r_{b} } \right)^\frac{3}{2} $$

The answer I was able to achieve was:

$$\frac{( T_{a} )^ \frac{2}{3}\,. r_{b} }{( T_{b} )^ \frac{2}{3} } = r_{a}$$

I originally believed my answer was correct but now a friend of mine is convinced it can be further simplified. Could anyone help me with this problem? Thanks in advance!

share|cite|improve this question
up vote 2 down vote accepted

Your friend is correct in saying that it can be further simplified down. Remember that $(\frac{a}{b})^n=\frac{a^n}{b^n}$

So, the fully simplified answer would be:


share|cite|improve this answer
I can't believe I overlooked such a basic thing! My head must be getting cloudy from all this math. Thanks! – ProfessorStealth Jan 25 '14 at 23:28
Not a problem. I find it kind of strange how you had to have expanded that out to get your answer, but didn't notice it. – Richard P Jan 25 '14 at 23:38

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.