I am self studying for my AP Calc exam. I have just started on integration and I need a few pointers for a few questions. So here it is....(adsbygoogle = window.adsbygoogle || []).push({});

y= (e^x)/(1+(e^x)^2)

So I set u=e^x

du=e^x

then I am stuck.

the second question is (btw [{( are all used as parentheses to make it abit less confusing)

y=(x^2)/[{(x^3)+1)}^12]

I setted u=(x^3)+1

du=3x^2

(1/3)du = (x^2)dx

(1/3)integral sign [1/(u^12)]du

stuck there after

and 3

y=[(lnx)^3]/x

do i set x as u? or lnx?

Last of all I have no clue on number 4 which is

y=sin(2x)*e^[cos(2x)]

Many thanks!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Anti differentiation using U sub help

**Physics Forums | Science Articles, Homework Help, Discussion**