Integral

Question

{(1-e^(-x))cos(x)}dx)/x

I read sir obleck work yesterday night but I couldn't respond as I was banned I don't know why

Any specific function to use here

Help me am bother not to fail this

Answer 1

Hmm. Now you are just dividing the integral by x?
Well, using integration by parts twice, you easily get
∫ e^-x cosx dx = 1/2 e^-x (sinx - cosx)
So, your integral works out
∫(1-e^-x) cosx dx = ∫ cosx dx - ∫ e^-x cosx dx
= sinx + 1/2 e^-x (cosx - sinx) + C

Now just divide all that by x

Answer 2

If you really are dividing by x inside the integral, you are out of luck.
∫ cosx/x dx and ∫ e^x/x dx cannot be done using the normal elementary functions. They are special functions defined by the integral.

In any case, go to wolframalpha.com and type in your function. It will show you what it thinks you typed, and if you scroll down, you will come to its integral.

Answer 3

The second part is what I need I knew this wasn't something that can be done elementary.......

Thanks anyway have given up already...

This is beyond me for now.........