# How do you factor x^4-16?

Use $\left({a}^{2} - {b}^{2}\right) = \left(a - b\right) \left(a = b\right)$
${x}^{4} - 16 = \left({x}^{2} - 4\right) \left({x}^{2} + 4\right) = \left(x + 2\right) \left(x - 2\right) \left({x}^{2} + 4\right)$