Posted by Ashley J on Tuesday, June 1, 2010 at 10:06pm.
The first one is the difference of cubes a^3 - b^3 = (a-b)(a^2 + ab + b^2) so 8y^3 - 27 = (2y-3)(4y^2 + 6y + 9) the second doesn't factor over the real numbers.