18/02/13 01:50:17.06 ZOqrSE8B.net
>>780 >>787
1もバカ問？
∫[0,∞) 1/(1+xx) dx = ［ arctan(x）] (x=0,∞）= π/2 = 1.570796326795…
∫[0,∞) 2sin(x)/(1+xx) dx = Ei(1)/e - Ei(-1)e = 1.29352224556…
∫[0,∞) sin(x)^2 /(1+xx) dx = (π/2e) sinh(1）= (π/4) {1 - e^(-2)} = 0.6791060805…
答え 3.