Suppose that a polynomial function of degree 4 with rational coefficients has - 2, - 6, - 5-i as zeros. Find the other zero.

complex roots (zeros) occur in conjugate pairs __ if 7+4i is a zero, then 7-4i is also a zero

for the coefficients to be rational; any irrational zeros (sqrt (7)) must have a conjugate, so - sqrt (7) is also a zero