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    Here are 4 terms used to describe the roots of a quadratic equation
    (1) real (2) unequal (3) equal (4) non-real

    Which of them describes the roots of 2x^2-3x+1=0?
    A (4) only
    B (3) only
    C (1) and (3)
    D (1) and (2)
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    (Original post by ralph123456)
    Here are 4 terms used to describe the roots of a quadratic equation
    (1) real (2) unequal (3) equal (4) non-real

    Which of them describes the roots of 2x^2-3x+1=0?
    A (4) only
    B (3) only
    C (1) and (3)
    D (1) and (2)
    D
    Factorise -> (2x-1)(x-1)
    Roots = 1/2 and 1
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    Consider the discriminant b^2-4ac. If it is greater than zero, then your roots are real and different. If equal to zero, your roots are real and equal. If it is less than zero, then your roots are complex (and different). Can you see why?

    For your equation, the discriminant is 9-8=1>0, so your roots are real and unequal. The correct option is D.

    NOTE: I would not recommend solving the equation, as some other users have, as this is more work and, particularly with factorisation, not always possible.
 
 
 
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Updated: January 2, 2013
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