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Question
Find the values of k for the following quadratic equation, so that they have two equal roots.
2x2 + kx + 3 = 0
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Solution
2x2 + kx + 3 = 0
Comparing equation with ax2 + bx + c = 0, we get
a = 2, b = k and c = 3
Discriminant = b2 - 4ac
= `(k)^2 - 4xx2xx3`
= k2 - 24
For equal roots,
Discriminant = 0
k2 - 24 = 0
k2 = 24
k = `±sqrt24`
k = `±2sqrt6`
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