Integration result: undefined
I've found this problem on twitter (original tweet by @mrdardy). Maybe a bug?
In Geogebra the command Integral(ℯ^x / ((ℯ^x)² + 1), 0, a) (where "a" is a slider) gives the correct result up to a=711.9198039 and becomes undefined beyond that value. Why? I know the integral should converge to pi/4 for a->inf.