1-e-pi-cos-lnx-x-dx-

Question Number 91904 by Ar Brandon last updated on 03/May/20

\int_{1}^{e^{π}} \frac{\cos (lnx)}{x} dx

Commented by Prithwish Sen 1 last updated on 03/May/20

put \ln (x) = t

Commented by Ar Brandon last updated on 03/May/20

Okay, let me try . Thanks

Commented by mathmax by abdo last updated on 03/May/20

I = \int_{1}^{e^{π}} \frac{c o s (l n x)}{x} d x v h a n g e m e n t l n x = t g i v e

I = \int_{0}^{π} \frac{c o s (t)}{e^{t}} e^{t} d t = \int_{0}^{π} c o s t d t = {[s i n t]}_{0}^{π} = 0

Answered by Ar Brandon last updated on 03/May/20