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Question
Discuss the nature of the roots of the following quadratic equations : x2 – 4x – 1 = 0
Solution
x2 – 4x – 1 = 0
Here a = 1, b = -4, c = -1
∴ D = b2 - 4ac
= (-4)2 - 4 x 1 x (-1)
= 16 + 4
= 20
∵ D > 0
Roots are real and distinct.
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