Question 967519
find all the zeroes of the polynomial 2x³+5x²-28x-15
use rational roots theorem with synthetic division:
..0..|....2.....5......-28.....-15.....
..1..|....2.....7......-21.....-36
..2..|....2.....9......-11.....-37
..3..|....2....11.......5........0 (3 is a zero)
f(x)=(x-3)(2x^2+11x+5)=(x-3)(2x+1)(x+5)

zeros are: -5, -1/2, and 3