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    The roots of the quadratic equation 2x2x^2x2​-x-3=0 are:
    Question

    The roots of the quadratic equation 2x2x^2​-x-3=0 are:

    A.

    1,-32\frac{3}{2}​​

    B.

    -1,32\frac{3}{2}

    C.

    1, 32\frac{3}{2}

    D.

    -1,-32\frac{3}{2}

    Correct option is B

    Given: 

    2x2x3=0 2x^2-x-3=0 

    Formula used:

    Discrimanant (D) = b24acb^2 - 4ac​​

    x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}​​

    Solution:

    Here : a=1,b=1,c=3a=1 , b = -1, c= -3 

    D = b24acb^2 - 4ac  = (1)24(2)(3)=1+24=25(−1) 2 −4(2)(−3)=1+24=25

    Substitute the value in above formula:

    x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = (1)±252(2)=1±54 \frac{-(-1) \pm \sqrt{25}}{2(2)} = \frac{1 \pm 5}{4} 

    Solve the root:

    x1=1+54=64=32x_1 = \frac{1 + 5}{4} = \frac{6}{4} = \frac{3}{2} 

    x2=154=44=1x_2 = \frac{1 - 5}{4} = \frac{-4}{4} = -1 

    So the root of quadratic equation is  32,1\frac{3}{2}, -1

    Thus the correct answer is (B) 

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