原函数=∫e^x/x^2dx只是这恐怕不能初等积分,可用级数法来积分：e^x=1+x+x^2/2!+x^3/3!+x^4/4!+.e^x/x^2=1/x^2+1/x+1/2!+x/3!+x^2/4!+...积分得原函数=-1/x+ln|x|+x/2!+x^2/(2*3!)+x^3/(3*4!)+.+C...