# integration of square root ?

• Sep 6th 2009, 12:14 AM
Zachary
integration of square root ?
$\int{\sqrt{\frac{a^2b^2x^2-b^2x^2}{a^2}}}dx$

• Sep 6th 2009, 12:27 AM
mr fantastic
Quote:

Originally Posted by Zachary
$\int{\sqrt{\frac{{{a^2b^2x^2-b^2}}x^2}{a^2}}}dx$

Try simplifying the radical. Note that $\sqrt{x^2} = |x|$.
• Sep 6th 2009, 12:29 AM
CaptainBlack
Quote:

Originally Posted by Zachary
$\int{\sqrt{\frac{{{a^2b^2x^2-b^2}}x^2}{a^2}}}dx$

\int{\sqrt{\frac{{{a^2b^2x^2-b^2}}x^2}{a^2}}}dx

You seem to have too many {} for the post to mean what you think it means

CB
• Sep 6th 2009, 12:59 AM
Zachary
Quote:

Originally Posted by CaptainBlack

\int{\sqrt{\frac{{{a^2b^2x^2-b^2}}x^2}{a^2}}}dx

You seem to have too many {} for the post to mean what you think it means

CB

sorry for that! now is better.
• Sep 6th 2009, 02:40 AM
mr fantastic
Quote:

Originally Posted by Zachary
sorry for that! now is better.

The advice given in post #2 still applies.
• Sep 6th 2009, 04:36 AM
HallsofIvy
Mr fantastic's point being that $\sqrt{a^2b^2x^2-b^2x^2}= |bx|\sqrt{a^2- 1}$
• Sep 6th 2009, 08:48 AM
CaptainBlack
Quote:

Originally Posted by HallsofIvy
Mr fantastic's point being that $\sqrt{a^2b^2x^2-b^2x^2}= |bx|\sqrt{a^2- 1}$

..and what was meant to be implied in post 3 is that it seems unlikely that that was what was intended.

CB
• Sep 6th 2009, 01:59 PM
mr fantastic
Quote:

Originally Posted by CaptainBlack
..and what was meant to be implied in post 3 is that it seems unlikely that that was what was intended.

CB

Indeed. But the moral of the story for all OP's is that it's only the question that's actually posted that will get answered, even when this is not the question that was intended ....