Originally Posted by

**MechEng** Good afternoon,

I managed to work my way through this problem rather quickly, but wound up with an answer that I feel is not correct (at least according to my calculator).

I have:

$\displaystyle

\int{\frac{1}{\sqrt{x^2-4}}dx

$

I evaluate to:

$\displaystyle

\ln\mid \frac{x+\sqrt{x^2-4}}{2}\mid + C

$

It should be:

$\displaystyle

\ln\mid{x+\sqrt{x^2-4}}\mid + C

$

I am picking up the 2 in the denominator via $\displaystyle sec\theta = \frac{x}{2}$ and $\displaystyle tan\theta = \frac{\sqrt{x^2-4}}{2}$.

Can anyone tell me what it is that I'm doing wrong here?