Question

If one zero of the polynomial 14x2 – 42k2

x – 9 is negative of the other, find the value of k.

Answer 1

Answer:

Let α(



=0) be one zero of the quadratic polynomial f(x)=14x

2

−42k

2

x−9.

Then f(α)=0

or, 14α

2

−42k

2

α−9=0.......(1).

Then according to the problem,

f(−α)=0

or, 14α

2

+42k

2

α−9=0......(2).

Now, subtracting (2) from (1) we get,

84k

2

α=0

or, k

2

=0 [ Since α



=0]

or, k=0.

Answer 2

That eqn is not clear .I mean can't distinguish x² and 2x ...To make 'x²' deep press the number 2 ....Then post the question again...

I understood it's x² but the balance is not clear.... Sorry ...