# Help with Integral please!

• Mar 19th 2013, 11:32 AM
Help with Integral please!
Can someone please show me how to solve this integral? This problem looks easy, but for some reason is not.

PS - This is not Homework, it is for personal practice

Thank you very much.
• Mar 19th 2013, 11:37 AM
TheEmptySet
Re: Help with Integral please!
Quote:

Originally Posted by Shadow236
Can someone please show me how to solve this integral? This problem looks easy, but for some reason is not.

PS - This is not Homework, it is for personal practice

Thank you very much.

This is a u substitution.

Let $u=5s+4 \implies du=5ds \iff ds=\frac{du}{5}$

Putting this into the integral gives

$\int \frac{1}{\sqrt{5s+4}}ds=\int \frac{1}{\sqrt{u}}\frac{du}{5}=\frac{1}{5}\int u^{-\frac{1}{2}}du$

Now just use the power rule for integration and finsh. Post back if you get stuck
• Mar 19th 2013, 02:01 PM