if a,b,c are the roots of the equation: x^3 + 2x^2 + 3x + 3 = 0 then the value of

[a/(a+1)]^3 + [b/(b+1)]^3 + [c/(c+1)]^3 is?

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I know that this equation has one real root and two imaginary roots. the real root lies between -2 and 0. But unable to proceed further.