# factoring a large polynomial

• Oct 29th 2008, 05:54 PM
alaricepent
factoring a large polynomial
In completely factored form

\$\displaystyle a^2x^2-b^2y^2+b^2x^2-a^2y^2\$

is.......

a) \$\displaystyle (a-b)(a+b)(x^2+y^2)\$
b) \$\displaystyle (a^2+b^2)(x^2-y^2)\$
c) \$\displaystyle (a^2-b^2)(x^2+y^2)\$
d) \$\displaystyle (a+b)(x-y)\$
e) \$\displaystyle (a^2+b^2)(x+y)(x-y)\$

HELP!! (Thinking)
• Oct 29th 2008, 06:38 PM
Shyam
Quote:

Originally Posted by alaricepent
In completely factored form

\$\displaystyle a^2x^2-b^2y^2+b^2x^2-a^2y^2\$

is.......

a) \$\displaystyle (a-b)(a+b)(x^2+y^2)\$
b) \$\displaystyle (a^2+b^2)(x^2-y^2)\$
c) \$\displaystyle (a^2-b^2)(x^2+y^2)\$
d) \$\displaystyle (a+b)(x-y)\$
e) \$\displaystyle (a^2+b^2)(x+y)(x-y)\$

HELP!! (Thinking)

\$\displaystyle a^2x^2-b^2y^2+b^2x^2-a^2y^2\$

\$\displaystyle =a^2x^2+b^2x^2-a^2y^2-b^2y^2\$

\$\displaystyle =x^2(a^2+b^2)-y^2(a^2+b^2)\$

\$\displaystyle =(a^2+b^2)(x^2-y^2)\$

\$\displaystyle =(a^2+b^2)(x+y)(x-y)\$

Did you get it now???