Q) If 𝛼, β are zeroes of quadratic polynomial 5x2 + 5x + 1, find the value of
1. 𝛼2 + 𝛽2
2. 𝛼‾1 + 𝛽‾1
Ans: Given polynomial equation 5x2 + 5x + 1 = 0
The roots of the polynomial be α and β.
We know that sum of roots (α + β) =
α + β = = -1
Hence, α = -1 – β …………… (i)
Next, we know that the product of the roots (α x β) =
α . β = …………. (ii)
(1) Value of 𝛼2 + 𝛽2:
𝛼2 + 𝛽2 = (𝛼 + 𝛽)2 – 2 (α . β)
By transferring values from equations (i) and (ii), we get:
𝛼2 + 𝛽2 = (-1)2 – 2 )
= 1 – =
The value of 𝛼2 + 𝛽2 is
(2) Value of 𝛼-1 + 𝛽-1
𝛼-1 + 𝛽-1 =
=
By transferring values from equations (i) and (ii), we get:
𝛼-1 + 𝛽-1 = = – 5
Therefore, the Value of 𝛼-1 + 𝛽-1 is – 5.