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Question
Find the value of k for which the roots are real and equal in the following equation:
3x2 − 5x + 2k = 0
Solution
The given quadric equation is 3x2 − 5x + 2k = 0, and roots are real and equal
Then find the value of k.
Here, a = 3, b = −5 and c = 2k
As we know that D = b2 − 4ac
Putting the value of a = 3, b = −5 and c = 2k
= (−5)2 − 4 × (3) × (2k)
= 25 − 24k
The given equation will have real and equal roots, if D = 0
Thus,
25 − 24k = 0
24k = 25
k = `25/24`
Therefore, the value of k = `25/24`.
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