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Tan(x)integral from 0 to oo crashes my HP 40G. How about Hp 49G ?

I am crashing too!! What can the integral of sin, cos, or tan be, when integrated to infinity? Maybe Lewis Carroll could tell me.

Integral of Tan(x) is -ln(cos(x)) which has a singularity at x=pi/2 (and 3/2 pi, 5/2 pi etc). So the integral from 0 to x=pi/2 would be oo.
Although, you can calculate the Cauchy principal value (limit for x-> pi/2) of the integral from 0 to pi, which is 0.
Hopefully not to confusing eplained...

Greetings from Jena, Germany


would this singularity raise to oo if PI/2 is not exact? Is the exact-mode flag set? What about trying in Approximate mode?

I did not try it, but I thought I could suggest it.

Regards from Brazil.