Question

If -1/2 is one zero of quadratic equation 2x²+kx+1 find the value of k.

Answer 1

Hey mate!

Here is your answer...

2x²+kx+1 = 0

x = -1/2

2(-1/2)² + k(-1/2)+1 = 0

2(1/4) -k/2 + 1 = 0

1/2-k/2+1 = 0

1-k+2/2= 0

-k+3 = 0

k = -3






Hope it helps...

Answer 2

Step-by-step explanation:

GIVEN:-)

→ One zeros of quadratic polynomial = -3.

→ Quadratic polynomial = ( k - 1 )x² + kx + 1.

Solution:-

→ P(x) = ( k -1 )x² + kx + 1 = 0.

→ p(-3) = ( k - 1 )(-3)² + k(-3) + 1 = 0.

=> ( k - 1 ) × 9 -3k + 1 = 0.

=> 9k - 9 -3k + 1 = 0.

=> 6k - 8 = 0.

=> 6k = 8.

$\large \boxed{=> k = \frac{8}{6} = \frac{4}{3} }$

Hence, the value of ‘k’ is founded .