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    Question

    If (3x - y) = 3, xy = (2/3), then find the value of

    {x3 - (y3/27)}
    A 5/3 Correct Answer Incorrect Answer
    B 7/3 Correct Answer Incorrect Answer
    C 5/7 Correct Answer Incorrect Answer
    D 7/3 Correct Answer Incorrect Answer

    Solution

    Given, 3x - y = 3 ........ (I) On dividing equation (I) by '3', we have; {x - (y/3)} = 1 On cubing both sides, we have; x3 - (y3/27) - 3 X x X (y/3) X {x - (y/3)} = 1 Or, x3 - (y3/27) = 1 + xy X 1 Or, x3 - (y3/27) = 1 + (2/3) Or, x3 - (y3/27) = (5/3)

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