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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) =  If 𝛼, β are zeroes of

If 𝛼, β are zeroes of   α + β =  If 𝛼, β are zeroes of = -1

Hence, α = -1 – β …………… (i)

Next, we know that the product of the roots (α x β) = If 𝛼, β are zeroes of

If 𝛼, β are zeroes of α . β = If 𝛼, β are zeroes of…………. (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 If 𝛼, β are zeroes of)

= 1 – If 𝛼, β are zeroes of  = If 𝛼, β are zeroes of

The value of 𝛼2 + 𝛽2 is If 𝛼, β are zeroes of

(2) Value of 𝛼-1 + 𝛽-1

𝛼-1 + 𝛽-1  = If 𝛼, β are zeroes of

= If 𝛼, β are zeroes of

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

𝛼-1 + 𝛽-1  = If 𝛼, β are zeroes of = – 5

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

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