Question

How do you solve `5x^3-3x^2-20x+12=0`?

Answer 1

You can factorise by grouping in pairs. See below

Explanation:

`5x^3-3x^2-20x+12=0`

`x^2(5x-3)-4(5x-3)=0`

`(x^2-4)(5x-3)=0`

`(x+2)(x-2)(5x-3)=0`

`x=+-2, 3/5`