# How do you factor x^2 - 1?

Jul 9, 2015

${a}^{2} - {b}^{2} = \left(a + b\right) \left(a - b\right)$
And since $1 = {1}^{2}$:
${x}^{2} - 1 = \left(x + 1\right) \left(x - 1\right)$