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Question
Without solving the following quadratic equation, find the value of ‘p’ for which the roots are equal.
px2 – 4x + 3 = 0
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Solution
px2 – 4x + 3 = 0
Here a = p, b = −4 and c = 3
Given equation has equal roots
Then D = 0
`=>` b2 – 4ac = 0
`=>` [–4]2 – 4(p)(3) = 0
`=>` 16 – 12p = 0
`=>` –12p = –16
`=> p = (-16)/(-12) = 4/3`
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