Question
Sun June 24, 2012 By: Soma

if the polynomial 6x^3+16x^2+px-5 is exactly divisible by 3x+5,how to find the value of p?

Expert Reply
Sun June 24, 2012
Given, polynomial p(x) = 6x3+16x2+px-5 is exactly divisible by 3x+5. This means the remainder is 0 when p(x) is divided by 3x + 5.
So, p(-5/3) = 0
6(-5/3)3+16(-5/3)2+p(-5/3)-5 = 0
6(-125/27)+16(25/9)+p(-5/3)-5 = 0
6(-125) + 16(25)(3) + p (-5) (9) - 5(27) = 0
-750 + 1200 - 45p - 135 = 0
45p = 315
p = 7
Home Work Help