Question

for what value of 'a' is the polynomial x³+2x²-3ax-8 is a multiple of x-4​

Answer 1

p(4) = (4)³ + 2(4)² - 3(4)a -8

0 = 64 + 32 - 12a - 8

0 = 88 -12a

-88 = -12a

a = 7.4 (approx)