How do you factor $x^{3} - 4 x^{2} - 36 x + 144$ $x^3-4x^2-36x+144$ by grouping?

Question

2350 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-08-07T11:41:33

$x^{3} - 4 x^{2} - 36 x + 144 = (x + 6) (x - 6) (x - 4)$ $x^3-4x^2-36x+144 = (x+6)(x-6)(x-4)$

$x^{3} - 4 x^{2} - 36 x + 144$ $x^3-4x^2-36x+144$

= $x^{2} (x - 4) - 36 (x - 4)$ $x^2(x-4)-36(x-4)$

= $(x^{2} - 36) (x - 4)$ $(x^2-36)(x-4)$

= $(x^{2} - 6 x + 6 x - 36) (x - 4)$ $(x^2-6x+6x-36)(x-4)$

= $(x (x - 6) + 6 (x - 6)) (x - 4)$ $(x(x-6)+6(x-6))(x-4)$

= $(x + 6) (x - 6) (x - 4)$ $(x+6) (x-6) (x-4)$

How do you factor x3−4x2−36x+144x^3-4x^2-36x+144 by grouping?