Mathematics
If the quadratic equation kx2 + kx + 1 = 0 has real and distinct roots, the value of k is :
0
4
0 and 4
0 or 4
Quadratic Equations
11 Likes
Answer
Comparing equation kx2 + kx + 1 = 0, with ax2 + bx + c = 0 , we get :
a = k, b = k and c = 1.
Since, quadratic equation has real and distinct roots.
∴ D > 0
∴ b2 - 4ac > 0
⇒ k2 - 4 × k × 1 > 0
⇒ k2 - 4k > 0
⇒ k(k - 4) > 0
⇒ k > 0 or k > 4.
Considering k > 0,
k = 4 can give real and distinct roots for kx2 + kx + 1 = 0.
Hence, Option 2 is the correct option.
Answered By
7 Likes