How to integrate (x^2+1)^2/(x^2+1)^2?

The integral of (x^2+1)^2/(x^2+1)^2 is x + C.

When integrating a function, it is important to simplify the expression as much as possible before attempting to integrate. In this case, we can simplify the expression by cancelling out the (x^2+1)^2 terms in the numerator and denominator, leaving us with:

∫(x^2+1)^2/(x^2+1)^2 dx = ∫1 dx

Integrating 1 with respect to x gives us x, so the final answer is:

∫(x^2+1)^2/(x^2+1)^2 dx = x + C

where C is the constant of integration.