Question

Show that ( − 3) is a factor of () = 3 + 2 − 17 + 15 by using factor theorem.​

Answer 1

x³ - x² - 17x + 15

x = -5

Now we we will put 5 instead of x

(-5)³ - (-5)² - 17(-5) + 15

125 - 25 + 85 +15

100 - 100

0

(x + 5) is a factor

(x² - 4x + 3)(x+5)

(x+5)(x+1)(x–3)