New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    In each question two equations are provided. On the basis of these you have to find out the relation between p and q. Give answer.

    I. p2 +7p + 10 = 0 II. q2- q

    – 6 = 0
    A if p = q Correct Answer Incorrect Answer
    B if p > q Correct Answer Incorrect Answer
    C if q > p Correct Answer Incorrect Answer
    D if p ≥ q Correct Answer Incorrect Answer
    E if q ≥ p Correct Answer Incorrect Answer

    Solution

    I. p2+7p + 10 = 0,
    p2+ 5p + 2p + 10 + 6 = 0; or
    p( p+5) + 2( p+5) = 0
    (p+2)( p+5) = 0, or p = -2 or = -5,
    II. q2 - q – 6 = 0;
    q2 – 3q + 2q – 6 = 0
    q(q-3) + 2(q -3) = 0 or, q = -2 or 3
    Hence, q ≥ p
    Alternate Method:
    if signs of quadratic equation is +ve and +ve respectively then the roots of equation will be -ve and -ve.
    So, roots of first equation = p = -2, -5
    if signs of quadratic equation is -ve and -ve respectively then the roots of equation will be +ve and -ve. (note: -ve sign will come in smaller root)
    So, roots of second equation = q = -2, 3
    After comparing roots of quadratic eqution we can conclude that q ≥ p.

    Practice Next

    Relevant for Exams: