How do you factorise x2 -1?

Answer 1

To factorise (x^2 - 1), you can recognize it as a difference of squares, which follows the formula (a^2 - b^2 = (a - b)(a + b)). Here, (a = x) and (b = 1). Thus, (x^2 - 1) can be factored as ((x - 1)(x + 1)).