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Question
Find the discriminant of the following equations and hence find the nature of roots: 3x2 + 2x - 1 = 0
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Solution
3x2 + 2x - 1 = 0
Here a = 3, b = 2, c = -1
∴ D = b2 - 4ac
= (2)2 - 4 x 3 x (-1)
= 4 + 12
= 16
∴ Discriminant = 16
∵ D > 0
∴ Roots are real and distinct.
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