Factorising — Difference of Two Squares

Simplify algebraic expressions, expand binomial products and factorise monic quadratic expressions.

Two perfect squares separated by a minus sign. Never a plus.

Worked example

1. Identify perfect squares separated by a minus$x^{2} - 1$
2. Write two brackets, a different sign in each$(\ \ \ + \ \ \ )(\ \ \ - \ \ \ )$
3. Put the square root of each term into both brackets$(x+1)(x-1)$
4. Simplify if possible$(x+1)(x-1)$

Practice