求解一道微积分题,谢谢!

2025-03-01 06:04:43
推荐回答(1个)
回答1:

x=1/t,
dx=-dt/t^2,
dx/[x^3(1+x^2)]
=-dt/[t^2*1/t^3*(1+1/t^2)]
=-t^3dt/(1+t^2).
选B.