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Question
Find the nature of the roots of the following quadratic equations: `x^2 - 2sqrt(3)x - 1` = 0 If real roots exist, find them.
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Solution
`x^2 - 2sqrt(3)x - 1` = 0
Here `a = 1, b = -2sqrt(3), c = -1`
∴ D = b2 - 4ac
= `(-2sqrt(3))^2 - 4 xx 1 xx (-1)`
= 12 + 4
= 16
∴ D > 0
∴ Roots are real and unequal.
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