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    Question

    If a + b + c = 11, ab + bc + ca = 3 and abc = -135, then

    what is the value of a³ + b³ + c³ ?
    A 929 Correct Answer Incorrect Answer
    B 925 Correct Answer Incorrect Answer
    C 827 Correct Answer Incorrect Answer
    D 823 Correct Answer Incorrect Answer

    Solution

    => a3 + b3 + c3 – 3abc = (a + b + c) [(a + b + c)2 – 3(ab + bc + ca)] => a3 + b3 + c3 – 3(-135) = 11 [(11)2 – 3(3)] => a3 + b3 + c3 + 405 = 1232 => a3 + b3 + c3 = 1232 – 405 => => a3 + b3 + c3 = 827

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