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    Question

    If a and b are the roots of x² + x – 2 = 0, then the

    quadratic equation in x whose roots are 1/a + 1/b and ab is
    A 2x² + 3x – 2 = 0 Correct Answer Incorrect Answer
    B 2x² – 5x + 2 = 0 Correct Answer Incorrect Answer
    C 2x² + 5x – 2 = 0 Correct Answer Incorrect Answer
    D 2x² – 3x + 2 = 0 Correct Answer Incorrect Answer

    Solution

    ATQ,

    Find Roots of x2+x−2 = 0: Using the quadratic formula, the roots are: a=1,b=−2 Find New Roots: First root:

    Second root: ab = −2

    Find New Quadratic Equation:

    Sum of roots:

    Product of roots:

    Using the formula:

    Multiply by 2 to remove fraction:

    Practice Next

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