Question

When adding and subtracting rationals, what should be the first thing you find? How do you find it?

Answer 1

Typically you should factor the denominators first, as it will make getting the least common multiple easier. For the first denominator, you can factor out x^2, the second denominator is a perfect square, (x^2+1) (x^2-1) and the last denominator is already simplified. It appears the denominators don't have a common factor though, so yes, you would have to multiply each of the denominators out.