Q27 of 40 Page 1

If α and β are the zeros of the polynomial f(x) = x2 - 4x – 5 then find the value of α2 + β2.

For given equation, we have

α + β = 4 [-b/a]


αβ = -5 [c/a]


Now, α2 + β2 = (α + β)2 – 2αβ


= (4)2 – 2(-5)


= 16 + 10 = 26


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