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For what values of 'K' does the equation have one real solution?x2+2Kx+4=0x^2 +2Kx+4=0x2+2Kx+4=0​
Question

For what values of 'K' does the equation have one real solution?

x2+2Kx+4=0x^2 +2Kx+4=0

A.

-2, 0

B.

2, -2

C.

0

D.

2, 0

Correct option is B

Given:
The quadratic equation is:
x2+2Kx+4=0x^2 + 2Kx + 4 = 0​​
Concept Used:
A quadratic equation ax2+bx+c=0ax^2 + bx + c = 0​ has one real solution (or a repeated real root) when its discriminant (D) is equal to zero.
the discriminant D is given by:
D=b24acD = b^2 - 4ac​​
Solution:
Identify a, b, and c from the equation:
a = 1
b = 2K
c = 4
Substitute these values into the discriminant formula:
D=(2K)2414D = (2K)^2 - 4 \cdot 1 \cdot 4​​
D=4K216D = 4K^2 - 16​​
4K216=04K^2 - 16 = 0​​
4K2=164K^2 = 16​​
K2=4K^2 = 4​​
K=±2K = ±2​​
Thus, The values of K for which the equation has one real solution are K = 2 and K = -2.

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