CBSE
2026
Class Class 10 · Mathematics
1 Marks · Mcq
✅ Verified
If the roots of the quadratic equation $\sqrt{3}x^2 - kx + 2\sqrt{3} = 0$ are real and equal, then the value(s) of $k$ is/are :
A. $\pm\sqrt{24}$
B. $0$
C. $4$
D. $-5$
✅ Answer & Solution
✅ Correct Answer: A
Step 1: For real and equal roots, discriminant $D = 0$.
Step 2: Here $a = \sqrt{3}$, $b = -k$, $c = 2\sqrt{3}$.
$$D = b^2 - 4ac = k^2 - 4(\sqrt{3})(2\sqrt{3}) = k^2 - 24$$
Step 3: $$k^2 - 24 = 0 \Rightarrow k^2 = 24 \Rightarrow k = \pm\sqrt{24}$$
Correct option : (A)
✅ Verified by Super Admin