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

Answer:

k = 0.

Step-by-step explanation:

Given :

$\large f(x)=4x^2-8kx-9$

And one zero is negative of the other.

We have to find value of k.

$\large \text{Let one zero be \alpha so other will be -\alpha }$

We know sum of two zero = - b / a

where b is coefficient of x and a is coefficient of $x^2$

Putting values here we get

$\large \alpha-\alpha=\dfrac{-8k}{4}\\\\\\\large 0=-2k\\\\\\\large k=0$

Thus we get k = 0.

Answer 2

Answer :-

→ k = 0 .

Step-by-step explanation :-

It is given that,

→ One zeros of the given polynomial is negative of the other .

Let one zero of the given polynomial be x .

Then, the other zero is -x .

•°• Sum of zeros = x + ( - x ) = 0 .....

But, Sum of zeros = -( coefficient of x )/( coefficient of x² ) = - ( -8k )/4 .

==> 2k = 0 .

==> k = 0/2 .

•°• k = 0 .

Hence, it is solved.