Find    .

i guess itz non integrable

substitutin pi/2e^x = t

thus pi/2e^x dx=dt

in d question multiply and divide by e to d power x

thus u get d integral as ..2/pi(sint/t)dt

sint/t is nt cont at t =0 .....................

thus itz nt integrable

correct me if i m wrng ....

If it is a definite integral with limits 0 to inf or -inf to inf then it is certainly integrable in closed form.

Do u want that ?

To @ Deedee

Plz note that discontinuity at an isolated point does not make a fn non-integrable , e.g. U have certainly done integration involving box fn ,  is not it ?

Now that box fn ( Greatest integer fn ) is discontinuous corresponding to each integral point .

Secondly, pay attention to the redundant term ( pi/2 ) in the final form of ur obtained simplified form !!!

I doubt that it can be integrated if limits are not given.

More information about the Si(t0 function:

http://mathworld.wolfram.com/SineIntegral.html