Question

If one zero of the quadratic polynomial $f(x) = 4x^{2} -8kx-9$ is negative of the other, find the value of k.

Answer 1

SOLUTION :

Given : The quadratic polynomial f(x)= 4x² - 8kx- 9

Let, the two zeroes of the polynomial f(x)= 4x² - 8kx- 9 be α and β =  -α.

On comparing with ax² + bx + c,

a = 4 , b= 8k , c= -9

Sum of the zeroes = −coefficient of x / coefficient of x²

α + β  = -b/a = -8k /4

α - α =  -8k /4

0 = -8k /4

0 = - 8k  

k = 0/-8

k = 0

Hence, the value of k is 0.

HOPE THIS ANSWER WILL HELP YOU….

Answer 2

Heya mate, Here is ur answer

Let the two zeroes be a and B.

$<b>Read a= alpha </b>$

$<b>B=Beta </b>$

A/Q

B=-a

F(x) = 4x^2 -8kx-9

Here a = 4 , b= -8k and c=-9

We know that

Sum of the zeroes (a+B)= -b/a

a+(-a) = -(-8k)/4

a-a=8k/4

0=8k/4

0×4=8k

0=8k

0/8=K

0=K

$<b><u>Hence the value of K is 8 . </b></u>$