if x+3is factor of x^3+2x^2-ax-18 find value of 'a'
Require that [x^3+2x^2-ax-18]/(x+3) have zero remainder. Apply polynomial long division. If you are unfamiliar with the method, Google it.
a = -9 is the answer. The quotient is then x^2 -x -6
a = -9 is the answer. The quotient is then x^2 -x -6