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    Question

    If x² - 2x + 1 = 0, then find the value of (x² +

    x⁻²)(x³ + x⁻³).
    A 2 Correct Answer Incorrect Answer
    B 3 Correct Answer Incorrect Answer
    C 4 Correct Answer Incorrect Answer
    D 6 Correct Answer Incorrect Answer

    Solution

    x² - 2x + 1 = 0
    x² + 1 = 2x
    By dividing both side by 'x' we get,
    (x + 1/x) = 2
    So, x = 1 [Since we know if (x + 1/x) = 2, then the value of 'x' is 1]
    Now, (x² + x⁻²)(x³ + x⁻³) = (1 + 1)(1 + 1) = 2 × 2 = 4

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