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

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  12. If the difference between the roots of the equation x^2+a x+1=0 is les...

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  13. Let a ,b , c ,p ,q be real numbers. Suppose alpha,beta are the roots o...

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  14. The quadratic equations x^2""-6x""+""a""=""0""a n d ""x^2""-c x""+""...

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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. Find the discriminant of the quadratic equation 2x^2-4x+3=0, and hence...

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  18. If the roots of the equation b x^2+""c x""+""a""=""0 be imaginary, t...

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  19. Let p and q real number such that p!= 0,p^3!=q and p^3!=-q. if alpha a...

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  20. solve 0=-1+2x+3x^2

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  21. Find the roots of x^2-6x-2=0

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