how do i work this out
Expand (x + 2) (x - 3) ( x + 5) =
( x^2 - x - 6) ( x + 5) =
x^3 - x^2 - 6x + 5x^2 - 5x - 30 =
x^3 + 4x^2 - 11x - 30
So
a = 4 and b = -30