Question : If α and β are the zeroes of the polynomial 4x2-4x+1, then 1/α + 1/β is ____________.
Doubt by Gauri
Solution :
4x2-4x+1
a = 4
b=-4
c=1
We know,
α + β = -b/a
α + β = -(-4)/4
α + β = 1 — (1)
α + β = -b/a
α + β = -(-4)/4
α + β = 1 — (1)
α β = c/a
α β = 1/4 — (2)
α β = 1/4 — (2)
Now,
1/α + 1/β
= (β+α)/αβ
= (α+β)/αβ
= (1)/(1/4) [From eq (1) and eq (2)]
= 4×1
1/α + 1/β
= (β+α)/αβ
= (α+β)/αβ
= (1)/(1/4) [From eq (1) and eq (2)]
= 4×1
= 4
∴ 1/α + 1/β = 4