是求∫[x/(x^2-x-2)]dx吧! 若是这样,则方法如下:
∫[x/(x^2-x-2)]dx
=∫{x/[(x-2)(x+1)]}dx
=(1/3)∫{[(x+1)-(x-2)]/[(x-2)(x+1)]}dx
=(1/3)∫[1/(x-2)]dx-(1/3)∫[1/(x+1)]dx
=(1/3)ln|x-2|-(1/3)ln|x+1|+C.
是求∫[x/(x^2-x-2)]dx吧! 若是这样,则方法如下:
∫[x/(x^2-x-2)]dx
=∫{x/[(x-2)(x+1)]}dx
=(1/3)∫{[(x+1)-(x-2)]/[(x-2)(x+1)]}dx
=(1/3)∫[1/(x-2)]dx-(1/3)∫[1/(x+1)]dx
=(1/3)ln|x-2|-(1/3)ln|x+1|+C.