How do you factor 81x^5y+24x^2y^4?

1 Answer
Jul 2, 2016

3x^2y(3x+2y)(9x^2 - 6xy +4y^2)

Explanation:

Always look for a common factor first, in this case, 3x^2y

3x^2y(27x^3 + 8y^3) " now this is the sum of cubes"

=3x^2y(3x+2y)(9x^2 - 6xy +4y^2)

Sum of cubes is given as:

(x^3 + y^3) = (x+y)(x^2 - xy + y^2)

Difference of cubes is given as:

(x^3 - y^3) = (x-y)(x^2 + xy + y^2)