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    Question

    If x² - 2x + 1 = 0, then find the value of (x³ +

    x⁻³)(x + x⁻¹).
    A 6 Correct Answer Incorrect Answer
    B 4 Correct Answer Incorrect Answer
    C 5 Correct Answer Incorrect Answer
    D 8 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, (x³ + x⁻³)(x + x⁻¹) = (1 + 1)(1 + 1) = 2 × 2 = 4

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