How do you simplify $7xy (x^2 + y) - 11 xy^2 (x^2 -1)$ ?

Question

2172 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-04-25T07:08:01

$7xy (x^2 + y) - 11 xy^2 (x^2 -1)$

We know that $color(blue)(a*(b+-c) = a*b +-a*c$

$= 7xy*x^2 + 7xy*y -11xy^2*x^2 - 11xy^2$

$= 7(x*x^2)*y + 7x(y*y) - 11(x*x^2)(y^2) - 11xy^2$

We also know that $color(blue)(a^m * a^n = a^(m+n)$

$= 7(x^(2+1))*y + 7x(y^(1+1)) - 11(x^(2+1))(y^2) - 11xy^2$

$= 7x^3y + 7xy^2 - 11x^3y^2 - 11xy^2$

$= 7x^3y + (7xy^2 - 11xy^2) - 11x^3y^2$

$= 7x^3y - 4xy^2 - 11x^3y^2$

$=color(green)( - 11x^3y^2 + 7x^3y - 4xy^2$

How do you simplify 7xy (x^2 + y) - 11 xy^2 (x^2 -1)7xy (x^2 + y) - 11 xy^2 (x^2 -1)?