if alpha and beta are the zeroes of polynomial f(x)=x^2-5x+4 ,find the value of 1/alpha+1/beta-2×alpha×beta
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p(x)=x²-4x-x+4=0
x(x-4)-1(x-4)=0
(x-4)(x-1)=0
∴ x=4 and x=1
So, α=4 and β=1
1/α+1/β-2αβ
1/4+1-8
1/4-7
1/4-28/4=-27/4
∴ The answer is -27/4 or -6.75
x(x-4)-1(x-4)=0
(x-4)(x-1)=0
∴ x=4 and x=1
So, α=4 and β=1
1/α+1/β-2αβ
1/4+1-8
1/4-7
1/4-28/4=-27/4
∴ The answer is -27/4 or -6.75
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