1.

If `alpha +beta =3, alpha^3 + beta^3 = 7`, then `alpha` and `beta` are the roots of

Answer» Here, `alpha^3+beta^3 = 7`
`=>(alpha+beta)^3 - 3alphabeta(alpha+beta) = 7`
`=>3^3-3alphabeta(3) = 7`
`=>9alphabeta = 20`
`=>alphabeta = 20/9.`
So, the equation will be,
`x^2-3x+20/9 = 0`
`=>9x^2-27x+20 = 0`
So,option `(b)` is the correct option.


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