Can someone help me evaluate this integral plz?

0 ⤊

integral dx/(pie(x^2 + 1))
how do i show that this equals 1

2007-03-08 13:31:54 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics

from negative infinity to infinity

2007-03-08 13:35:24 · update #1

Introduce substitution x = tg(y) then your integral becomes:
integral(from -pi/2 to pi/2)[(dy/cos^2(y))/(pi*(1/cos^2(y)))] = 1.

2007-03-08 13:51:13 · answer #1 · answered by fernando_007 6 · 0⤊ 0⤋