 In the following formulas, a and b may be any number, variable, expression, or any combination of number, variable, and expression.
 Given an expression to factor:
 Identify the expression to be in the form of one of the lefthandsides listed below.
 Factor the expression by the formula shown in the associated righthandside.
 Difference of Two Squares
 a^{2}  b^{2} = (a + b)(a  b)
 Perfect Square Trinomials
 a^{2} + 2ab + b^{2} = (a + b)^{2}
 a^{2}  2ab + b^{2} = (a  b)^{2}
 Sum of Two Cubes
 a^{3} + b^{3} = (a + b)(a^{2}  ab + b^{2})
 Difference of Two Cubes
 a^{3}  b^{3} = (a  b)(a^{2} + ab + b^{2})
