Question

Find s cubic function with the given zeros -7 5 -3

Answer 1

If the zeros are -7, 5, and -3, then the factors are (x+7), (x-5), (x+3).  We have to multiply all those together to get a third degree polynomial.  Multiplying out the first 2, we get $(x+7)(x-5)=x^2+2x-35$.  Now we'll multiply in that last factor:  $(x^2+2x-35)(x+3)=x^3+5x^2-29x-105$.  There's your third degree polynomial!!