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) =  \frac{-b}{a}

\therefore   α + β =  \frac{-(5)}{5} = -1

Hence, α = -1 – β …………… (i)

Next, we know that the product of the roots (α x β) = \frac{c}{a}

\therefore α . β = \frac{1}{5}…………. (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 (\frac{1}{5})

= 1 – \frac{2}{5}  = \frac{3}{5}

The value of 𝛼2 + 𝛽2 is \frac{3}{5}

(2) Value of 𝛼-1 + 𝛽-1

𝛼-1 + 𝛽-1  = (\frac{1}{\alpha}) + (\frac{1}{\beta})

= \frac{\alpha + \beta}{\alpha . \beta}

By transferring values from equations (i) and (ii), we get:

𝛼-1 + 𝛽-1  = \frac{-1}{\frac{1}{5}} = – 5

Therefore, the Value of 𝛼-1 + 𝛽-1 is – 5.

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