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Question
Find the values of k for which the roots are real and equal in each of the following equation:
kx2 + 4x + 1 = 0
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Solution
The given quadric equation is kx2 + 4x + 1 = 0, and roots are real and equal
Then find the value of k.
Here, a = k, b= 4 and c = 1
As we know that D = b2 - 4ac
Putting the value of a = k, b= 4 and c = 1
D = (4)2 - 4(k)(1)
= 16 - 4k
The given equation will have real and equal roots, if D = 0
Thus,
16 - 4k = 0
4k = 16
k = 16/4
k = 4
Therefore, the value of k = 4.
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