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Question
Find the discriminant of the following equations and hence find the nature of roots: 2x2 + 15x + 30 = 0
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Solution
2x2 + 15x + 30 = 0
Here a = 2, b = 15, c = 30
∴ D = b2 - 4ac
= (15)2 - 4 x 2 x 30
= 225 - 240
= -15
∴ Discriminant = -15
∵ D < 0
∴ Root are not real.
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