Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
对于 integrate 2x(x^2 + 1)^3 dx ，哪个替换是适当的？
对于 integrate 2x(x^2 + 1)^3 dx ，哪个替换是适当的？
Natural Language
Math Input
Extended Keyboard
