Question

Find the value of k if ( x-3) is a factor of 2x2-kx+1.

Answer 1

Let,

$f(x) = 2 {x}^{2} - kx + 1$

By factor theorem, if (x-3) is a factor of f(x), then, f(3) will be equal to zero.

Hence, reqd. equation;

$f(3) = 18 - 3k + 1 = 0 \\ = > - 3k = - 19 \\ = > k = \frac{19}{3}$

HOPE THIS COULD HELP!!!

Answer 2

Answer:

k = 19/3

Step-by-step explanation:

Let p(x) = 2x^2 - kx + 1

&

f(x) be x - 3 = 0.

Then , x - 3 = 0.

Therefore x = 3 .

Also, p(3) should be 0 since g(x) is a factor of p(x).

So, p(3) = 2 × 3^2 - kx + 1 = 0 .

=> 2 × 9 - 3 × k + 1 = 0.

=> 18 - 3k = -1 .

=> -3k = -19.

Therefore k = 19/3.

Therefore the value of k is 19/3.