Calculus Integral Help
the problem is find the antiderivative of x/sqrt(1-x^4).
First I made x^4 into (x^2)^2 and then used U-substitution to get 2x.
Next, i multiplied integral by constant of 1/2 and made the x on top a 2x. Then it became 1/sqrt(1-u^2), whose antiderivative would be arscsin.
So my answer was 1/2 * arcsin(x^2). Being a worrywart, I checked my answer using an online integral calculator and they said the answer was -(1/2) * arctan(x^2)...did i mess up somewhere?
here is the site i used: http://www.integral-calculator.com/
March 11, 2014
4 Comments • Newest first
Your answer is right, you may have input the wrong numbers into the website.
you forgot chain rule
edit: i screwed up.. your answer should be correct
Your answer is right according to wolfram alpha.
Without putting too much thought into it, seems like trig substitution might be your friend here.
Try hypotenuse of 1, a side of x^2, and you have your sq.rt(1 - x^4) side. Differentiating the expression involving x^2 and theta will give you your x dx too.
EDIT:
Didn't read entire post, your answer is correct OP. Try differentiating arcsin(x^2) and see what you get.