1 year ago
Last edited at 11:48PM on 12/9/2012
Try replacing x with 1 2 5 or 10 (because they are factors of the end 10) You'll find putting x=1 gives 1+2-13+10 = 0 , so (x-1) is one factor Do you know how to divide (x-1) into the cubic function ? You get (x-1) (x^2 + 3x -10) Do you know how to factorise a quadratic ? You get (x-1)(x+5)(x-2)
Sketch this with x intercepts at -5 and 1 and 2 Start from the bottom left up through x= -5, through (0,10), down through 1 and turn and up through 2 and off to top right of page.
The roots (solutions, intercepts) are x = -5 or 1 or 2