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meteor
Feb18-04, 06:52 PM
Can somebody show me how to integrate this:?


\int ln (sin x) dx


thanks

HallsofIvy
Feb18-04, 08:23 PM
Do you have any reason to believe that its anti-dervivative is an elementary function?

turin
Feb19-04, 10:19 PM
I tried a sloppy method that got me close:
1) use Euler's ID for sin(x)
2) factor out an exponential
3) write the ln as a sum of simpler ln's
4) do a substitution for one of the ln's

This got me to an integral I didn't know how to solve, but that is probably simpler in principle. The integrand is:
ln(u)/(1 - u)