# Multiplying and Dividing Polynomials?

• Dec 16th 2009, 04:11 PM
deekay930
Multiplying and Dividing Polynomials?
Simplifying?

I got the answer \$\displaystyle 36c^4b^6a^2\$for the problem \$\displaystyle (-2ab^5)(-6abc)(3c^3)\$.Could you show me how you would solve these expressions?

\$\displaystyle (-3a^2b^2+7)(-6ab+2)\$

\$\displaystyle (x+3)(2x^2+7x+1)\$
• Dec 16th 2009, 05:39 PM
NOX Andrew
To simplify the expression \$\displaystyle (-3a^2b^2 + 7)(-6ab + 2)\$, distribute both \$\displaystyle -3a^2b^2\$ and \$\displaystyle 7\$ into \$\displaystyle (-6ab + 2)\$. Then, add the result (because you were adding \$\displaystyle -3a^2b^2\$ and \$\displaystyle 7\$).

\$\displaystyle (-3a^2b^2 + 7)(-6ab + 2) = (-3a^2b^2)(-6ab + 2) + 7(-6ab + 2) = 18a^3b^3 - 6a^2b^2 - 42ab - 14\$

To simplify the expression \$\displaystyle (x + 3)(2x^2 + 7x + 1)\$, distribute both \$\displaystyle x\$ and \$\displaystyle 3\$ into \$\displaystyle (2x^2 + 7x + 1)\$. Then, add the result.

\$\displaystyle (x + 3)(2x^2 + 7x + 1) = x(2x^2 + 7x + 1) + 3(2x^2 + 7x + 1) = 2x^3 + 7x^2 + x + 6x^2 + 21x + 3\$

Combine like terms.

\$\displaystyle 2x^3 + 13x^2 + 22x + 3\$
• Dec 16th 2009, 05:41 PM
Stroodle
Hi there.

There's also some good explanations on how to do these here: Practical Algebra Lessons