If a and b are roots of the equation x2 + a x + b = 0, then a + b = A – InterviewSolution

InterviewSolution

1.

If a and b are roots of the equation x2 + a x + b = 0, then a + b = A. 1 B. 2 C. – 2 D. – 1

Answer»

Given a and b are roots of the equation x² + a x + b = 0

Here a = 1, b = a, c = b

Sum of the roots = a + b = – a/1

b = – 2a

Product of the roots

ab = b

a = 1

∴ b = – 2 x 1 = – 2

Now a + b = 1 + (– 2) = – 1

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