Specifically, ones that don't seem very straightforward. I've consulted my textbook, but it only gives me step-by-step examples for ones that have a GCF (such as 5x^4 + 40x). Sometimes I'm told to factor polynomials such as x^4 - 37x^2 + 36 and x^6 - 12x^4 + 48x^2 - 64 , and although I've used calculators to see what the answer would have been I can't figure out how to work it backwards... I've tried breaking up the polynomial, but that doesn't seem to work very well. :c