判断广义积分的敛散性,若收敛计算其值 1 .∫[2,+∞]1/(1-x^2) dx 1 .∫[-∞,+∞]1/(x²+2x+2) dx

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判断广义积分的敛散性,若收敛计算其值 1 .∫[2,+∞]1/(1-x^2) dx 1 .∫[-∞,+∞]1/(x²+2x+2) dx
判断广义积分的敛散性,若收敛计算其值 1 .∫[2,+∞]1/(1-x^2) dx 1 .∫[-∞,+∞]1/(x²+2x+2) dx

判断广义积分的敛散性,若收敛计算其值 1 .∫[2,+∞]1/(1-x^2) dx 1 .∫[-∞,+∞]1/(x²+2x+2) dx
∫[2,+∞]1/(1-x^2) dx
=1/2∫[2,+∞][1/(1-x) -1/(1+x)]dx
=-1/2∫[2,+∞][ 1/(1+x)-1/(x-1)]dx
=-1/2[ln(1+x)-ln(x-1)][2,+∞]
=-1/2ln[(1+x)/(x-1)][2,+∞]
=1/2*ln3
∫[-∞,+∞]1/(x²+2x+2) dx
=∫[-∞,+∞]1/[(x+1)^2+1] dx
=arctan(x+1)[-∞,+∞]