If roots of the equation x2 – bx + c = 0 be two consectutive integers, then b2 – 4c equals
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– 2
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3
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2
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1
D.
1
Let α, α + 1 be roots
α + α + 1 = b
α(α + 1) = c
∴ b2 – 4c = (2α + 1)2 - 4α(α + 1) = 1.
If roots of the equation x2 – bx + c = 0 be two consectutive integers, then b2 – 4c equals
– 2
3
2
1
D.
1
Let α, α + 1 be roots
α + α + 1 = b
α(α + 1) = c
∴ b2 – 4c = (2α + 1)2 - 4α(α + 1) = 1.
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If roots of the equation x2 – bx + c = 0 be two consectutive integers, then b2 – 4c equals
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