Identify Common Factor: Identify the common factor in both terms of the expression x3−81x. Both terms have an x in common, so we can factor out an x.
Factor Out 'x': Factor out the common x from the expression.x3−81x can be factored as x(x2−81).
Recognize Difference of Squares: Recognize that the expression inside the parentheses is a difference of squares. x2−81 can be factored further because it is a difference of squares (a2−b2), where a=x and b=9.
Factor Difference of Squares: Factor the difference of squares. x2−81factors into (x+9)(x−9).
Write Fully Factored Form: Write the fully factored form of the original expression.The factored form of x3−81x is x(x+9)(x−9).