∫dx/(x的三次方+8)
解法如下:
原式=∫dx/(x^3+2^3)
=∫dx/(x+2)(x^2-2x+4)
=(1/12)∫1/(x+2)dx+∫[(-1/12)x+(1/3)]/(x^2-2x+4) dx
=(1/12)ln(x+2)-(1/24)∫d(x^2-2x+4)/(x^2-2x+4)+(1/4)∫1/(x^2-2x+4)dx
=(1/12)ln(x+2)-(1/24)ln(x^2-2x+4)+(1/4)∫1/[(x-1)^2+3] dx
=(1/12)ln(x+2)-(1/24)ln(x^2-2x+4)+(√3/12)∫ d[√3(x-1)/3] / 1+[√3(x-1)/3]^2
=(1/12)ln(x+2)-(1/24)ln(x^2-2x+4)+(√3/12)arctan[√3(x-1)/3]+ C
以上答案仅供参考,如有疑问可继续追问!
口袋妖怪漆黑的魅影第8道馆在哪
第七道馆下来,要潜水才可以到达,。。。