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If alpha,beta be the roots of the equat...

If `alpha,beta ` be the roots of the equation `3x^2+2x+1=0,` then find value of `((1-alpha)/(1+alpha))^3+((1-beta)/(1+beta))^3`

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Let `(1-alpha)/(1+alpha)=ximpliesa=(1-x)/(1+x)`
So replacing `x` by `(1-x)/(1+x)` in the given equation we get
`3((1-x)/(1+x))^(2)+2((1-x)/(1+x))|+1=0impliesx^(2)-2x+3=0` …….i
It is clear that `(1-alpha)/(1+alpha)` and `(1-beta)/(1+beta)` are the roots fo Eq. (i)
`:.((1-alpha)/(1+alpha))+((1-beta)/(1+beta))=2`..........ii
and `((1-alpha)/(1+alpha))((1-beta)/(1+beta))=3`.......iii
`:.((1-alpha)/(1+alpha))^(3)+((1-beta)/(1+beta))^(3)=((1-alpha)/(1+alpha) +(1-beta)/(1+beta))^(3)-3`
`((1-alpha)/(1+alpha))((1-beta)/(1+beta))((1-alpha)/(1+alpha)+(1-beta)/(1+beta))=2^(3)-3.3.2=8-18=-10`
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ARIHANT MATHS-THEORY OF EQUATIONS-Exercise (Questions Asked In Previous 13 Years Exam)
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  2. In the quadratic equation ax^2 + bx + c = 0. if delta = b^2-4ac and al...

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  3. Let S denote the set of all polynomials P(x) of degree lt=2 such th...

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  15. How many real solutions does the equation x^7+14 x^5+16 x^3+30 x-560=0...

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  16. Suppose the cubic x^(3)-px+q has three distinct real roots, where pgt0...

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  17. The smallest value of k, for which both the roots of the equation, x^2...

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