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Question
Roots of a quadratic equation are 5 and – 4, then form the quadratic equation
Solution
Let α = 5 and β = – 4
α + β = 5 – 4 = 1
and α × β = 5 × (– 4) = – 20
∴ The required quadratic equation is
x2 – (α + β)x + αβ = 0
∴ x2 – (1) x + (– 20) = 0
∴ x2 – x – 20 = 0
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