Question

My teacher stop half way when writing the example,someone pls help me how to do them thxxx
Use the factor theorem to show:
c)x-2 is a factor of 5x^3 -17x^2 -28

d)3x+1 is a factor of 6x^3 +11x^2 -3x -2

Answer 1

recall that the Factor Theorem says that if m is a root of a polynomial, then (x-m) is a factor. So, fixing your typo
c) since 5*2^3 - 17*2^2 + 28 = 40-68+28 = 0
(x-2) is a factor of 5x^3 -17x^2+28

For (d) show that -1/3 is a root of your polynomial.