Answers>Maths>IB>Article

Integrate x^2/(1+x^2)dx

Unlike if we had just x in the numerature, here the chain rule will do us no good.  Integration by parts in this case also is little help - we end up with expressions at least as difficult as we started with.  For example:

Int x2/(1+x2)dx = x2tan-1x - Int 2x tan-1x dx

In this case, a very simple approach is to simply add and subtract 1 from the denominator:

Int x2/(1+x2)dx = Int (x2+1-1)/(1+x2)dx= Int (1+x2)/(1+x2) - 1/(1+x2)dx = Int 1 - 1/(1+x2)dx

From here, do you know know you to solve the problem?

LH

Related Maths IB answers

All answers ▸

Find the coordinates that correspond to the maximum point of the following equation: y = −16x^2 + 160x - 256


Given that y = -16x2​​​​​​​ + 160x - 256, find the value of x giving the maximum value of y, and hence give this maximum value of y.


How do you perform implicit differentiation?


Differentiate implicitly with respect to x the equation x^3*y^5+3x=8y^3+1