Question 966871
Use the rational zeros thereom to find all the zeros of each polynomial function. Use the zeros to factor f over the real numbers. 
F (x) = X^3 + 8x^2 + 11x -20
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use rational roots theorem and synthetic division

...0..|.....1.......8.......11.......-20...........
...1..|.....1.......9.......20.......0..(1 is a root)
f(x)=(x-1)(x^2+9x+20)=(x-1)(x+5)(x+4)
zeros are: -5, -4, 1