Question

    If P3 + 3P2 + 3P =

    7, then the value of P2+ 2P is –
    A 4 Correct Answer Incorrect Answer
    B 3 Correct Answer Incorrect Answer
    C 5 Correct Answer Incorrect Answer
    D 6 Correct Answer Incorrect Answer

    Solution

    P3 + 3P2 + 3P = 7
    P3 + 3P2 + 3P + 1= 8
    (P + 1)3 = (2) 3
    P + 1 = 2
    P = 1
    So, P2 + 2P = (1)2 + 2 × 1
    = 1 + 2 = 3

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