Expanding more than Two Binomials

Expanding more than two binomials is carried out by multiplying the binomials in steps. Multiply one binomial at a time against the expression.

Because you will be multiplying a binomial against a quadratic, it is easiest to use a table.

Example 1

Expand $(x + 3)(x -2)(x + 7)$

First multiply $(x+3)$ and $(x-2)$

Next multiply the answer $(x^2 + x - 6)$ by $(x + 7)$

Answer: $x^3 + 8x^2 + x - 42$

Expand $(x^2 + 2x - 4)(x^2 -2x + 4)$

Set it up as a table::

Answer: $x^4 - 4x^2 + 16x - 16$