Question

two zeros of the cubic polynomial ax^3 c+ 3x^2- b
x - 6 are -1 and -2 find the third zero and the value of a and b​

Answer 1

Step-by-step explanation:

Let p(x) = ax^3 c+ 3x^2- bx - 6

Now, (x-1) & (x-2) are zeroes of p(x)

So, p(-1) = 0

-a + 3 -b = 0

a+b = 3

Also, p(-2) = 0

-8a + 12 -b = 0

8a + b = 12

8a = 12-(3-a)

8a = 9+a

7a = 9

a = 9/7

b = 3-a = 3 - 9/7 = (21-9)/7 = 12/7