有理函数积分
∫xdx/(1-2x-x^2)
=∫xdx/[2-（x+1）^2]
=(1/2)∫(2x+2-2)dx/(1-2x-x^2)
=-(1/2)∫d(1-2x-x^2)/(1-2x-x^2)-∫dx/[2-（x+1）^2]
=-(1/2)ln│1-2x-x^2│+∫d（x+1)/[（x+1）^2-2]
=-(1/2)ln│1-2x-x^2│+√2/4ln│（x+1-√2)/（x+1+√2）│+C
∫xdx/(1-2x-x^2)RT
有理函数积分
∫xdx/(1-2x-x^2)
=∫xdx/[2-（x+1）^2]
=(1/2)∫(2x+2-2)dx/(1-2x-x^2)
=-(1/2)∫d(1-2x-x^2)/(1-2x-x^2)-∫dx/[2-（x+1）^2]
=-(1/2)ln│1-2x-x^2│+∫d（x+1)/[（x+1）^2-2]
=-(1/2)ln│1-2x-x^2│+√2/4ln│（x+1-√2)/（x+1+√2）│+C