Integrate the following fraction w.r.t. x: (sqrt(x^2 + 1)-sqrt(x^2 - 1))/(sqrt(x^4 - 1))

Notice the denominator can be factorised as the difference of two squares. The fraction can then be simplified by cancellation. The resulting fraction(s) can then be solved using the list of integrals in your formulae and tables book. The final answer: ln|x+sqrt(x+1)| - ln|x+sqrt(x-1)| + C, |x|>1. (I hope to further explain the steps taken to solve this question using the whiteboard!)