Solving Integral Problem: x(x2-4)1/2dx

[evilq17]

I am having problems figuring out how to do this integral.
$$\int$$x(x²-4)^1/2dx

I know what the answer is, but I am not sure how to get there. I am not sure if there is a method or if you just need to do it by logic. I tried integration by parts but I just can't get to something I can integrate.

Thanks.

 

[mathman]

try y=x²-4. Then dy=2xdx. Now you are left with integrating (y^1/2)/2. You should be able to do that.

 

[NoMoreExams]

You probably COULD do it by parts? But that's clearly overkill. Like mathman pointed out, this screams u-subst.

 

[evilq17]

Thanks. U substitution. Its been too long since I have done this. Thanks.