Question

the sums of two zeros of a polynomial p(x) is 3 and the third root is 7 p (x) = 3x³+bx²-cx+100 find the value of b​

Answer 1

Answer:

b = -30

Step-by-step explanation:

Let the zeroes of the polynomial p(x) be x, y and z.

p(x) = 3x³ + bx - cx + 100 = 0

= kx³ + lx² + mx + n = 0

where k = 3, l = b, m = -c, n = 100

We are given that,

x + y = 3 and z = 7

We know that, in a cubic equation,

Sum of zeroes = -(l)/k

= x + y + z = -(b)/3

= (x + y) + z = -b/3

= 3 + 7 = -b/3

= 10 = -b/3

-b = 30

b = -30

Hope it helped and you understood it........All the best