## anonymous 5 years ago complete the following integral or partial substitution with x tanx dx

1. anonymous

use integration by parts u = x dv = tanx du =dx v = -ln|cosx|

2. anonymous

wait nevermind that wont work i dont know if this has a simple anti-derivative

3. anonymous

Do integration by parts, Take the derivative of x and integral of tanx =$x \log|secx| - \int\limits_{}{}tanx$ =log|secs|(x-1)

4. anonymous

That should be secx*

5. anonymous

Sorry did a mistake, its not that simple, will think on it!

6. anonymous

= uv - integral v du so now all thats left is finding integral of ln(secx)

7. anonymous

let u= sec(x) , du = sec(x)tan(x) dx --> dx = du/ sec(x)tan(x)

8. anonymous

so integral ln(u) du / sec(x) tan(x) = $\frac{ \ln(u) du }{u \sqrt{u^2-1}}$

9. anonymous

yes , hmm, I dont think you can go anywhere there