Multiplication

Monomial by a Monomial

We begin this section by multiplying a monomial by a monomial. As you saw in the introduction, when working with monomials multiply the coefficients separately and then apply the exponent rules to each variable. Let’s try some examples.

Example 1 Multiply.
(3xy5)(-6x4y2)

Step 1. Group coefficients and like bases.

3 . -6 . x . x4 . y5 . y2

Step 2. Multiply coefficients & apply the product rule of exponents.

(3 . -6) x(1+4) y(5+2)

Step 3. Simplify.

-18x5y7


Example 2 Multiply.
(-12a2b3c4)(-3a2b2)

Step 1. Group coefficients and like bases.
-12 . -3 . a2 . a2 . b3 . b2 . c4

Step 2. Multiply coefficients & apply the product rule of exponents.
(-12 . -3) a(2+2) b(3+2)(c4)

Step 3. Simplify.
36a4b5c4