The polynomial function f(x) has the given zero. Find the other zeros.
F(x)=x^3+7x^2-3x-21;-7
+128474 x^3+7x^2-3x-21; -7 is a zero
Factor by grouping
x^2 ( x + 7) - 3(x + 7) = 0
(x + 7) ( x ^2 - 3 ) = 0
We know the zero of the first factor.....to find the zeroes of the second, we have
x^2 - 3 = 0 add 3 to both sides
x^2 = 3 take both positive and negative roots
x = ± √3
