The problem us integrate : $\displaystyle \frac{1}{x \sqrt{x^2+25}}dx $

I worked it out to here

$\displaystyle

\frac{5secT}{5tanT} dT$

1. Is this right so far and 2. Im a little confused on how to proceed from there.

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- Apr 20th 2010, 05:45 PMx5pyd3rxTrig Substitution
The problem us integrate : $\displaystyle \frac{1}{x \sqrt{x^2+25}}dx $

I worked it out to here

$\displaystyle

\frac{5secT}{5tanT} dT$

1. Is this right so far and 2. Im a little confused on how to proceed from there. - Apr 20th 2010, 05:57 PMDeadstar
Well, ASSUMING what you did up to there was right then use...

$\displaystyle \sec(x) = \frac{1}{\cos(x)}$

and

$\displaystyle \tan(x) = \frac{\sin(x)}{\cos(x)}$ - Apr 20th 2010, 06:01 PMTKHunny
Good start. Extra factor of 5 in the numerator.

- Apr 20th 2010, 06:18 PMx5pyd3rx
Thats kind of what i thought so it should be $\displaystyle \frac{secT}{5tanT}dT$

- Apr 21st 2010, 03:22 AMDeadstar