Algebra


  1. If   p × q = p + q +
    p
    , the value of 8 × 2 is :
    q









  1. View Hint View Answer Discuss in Forum

    p × q = p + q +
    p
    q

    ∴  8 × 2 = 8 + 2 +
    8
    2

    =10 + 4 = 14

    Correct Option: C

    p × q = p + q +
    p
    q

    ∴  8 × 2 = 8 + 2 +
    8
    2

    =10 + 4 = 14


  1. If a * b = 2a – 3b + ab, then 3 * 5 + 5 * 3 is equal to :









  1. View Hint View Answer Discuss in Forum

    a * b = 2a – 3b + ab
    ⇒  3 * 5 = 2 × 3 – 3 × 5 + 3 × 5 = 6
    5 * 3 = 2 × 5 – 3 × 3 + 3 × 5
    = 10 – 9 + 15 = 16
    Therefore, 3 * 5 + 5 *3
    = 6 + 16 = 22

    Correct Option: A

    a * b = 2a – 3b + ab
    ⇒  3 * 5 = 2 × 3 – 3 × 5 + 3 × 5 = 6
    5 * 3 = 2 × 5 – 3 × 3 + 3 × 5
    = 10 – 9 + 15 = 16
    Therefore, 3 * 5 + 5 *3
    = 6 + 16 = 22



  1. If p(x + y)2 = 5 and q(x - y)2 = 3 , then the simplified value of p2 (x + y)2 + 4pq xy – q2 (x - y)2 is :









  1. View Hint View Answer Discuss in Forum

    p(x + y)2 = 5

    ⇒ (x + y)2 =
    5
    p

    ⇒ q(x - y)2 = 3 ⇒ (x - y)2 =
    3
    q

    ∴ (x + y)2 - (x - y)2 =
    5
    -
    3
    pq

    ⇒ 4xy =
    5
    -
    3
    =
    5q - 3p
    pqpq

    ∴ p2 (x + y)2 + 4pq xy – q2 (x - y)2 = p2 .
    5
    + pq.
    (5q - 3p)
    - q2 .
    3
    ppqq

    p2 (x + y)2 + 4pq xy – q2 (x - y)2 = 5p + 5q – 3p – 3q = 2p + 2q

    Correct Option: B

    p(x + y)2 = 5

    ⇒ (x + y)2 =
    5
    p

    ⇒ q(x - y)2 = 3 ⇒ (x - y)2 =
    3
    q

    ∴ (x + y)2 - (x - y)2 =
    5
    -
    3
    pq

    ⇒ 4xy =
    5
    -
    3
    =
    5q - 3p
    pqpq

    ∴ p2 (x + y)2 + 4pq xy – q2 (x - y)2 = p2 .
    5
    + pq.
    (5q - 3p)
    - q2 .
    3
    ppqq

    p2 (x + y)2 + 4pq xy – q2 (x - y)2 = 5p + 5q – 3p – 3q = 2p + 2q


  1. If x = ³√7 + 3 then the vlaue of x3 - 9x2 + 27x - 34 is :









  1. View Hint View Answer Discuss in Forum

    x = ³√7 + 3
    ⇒ x - 3 = ³√7
    On cubing both sides ,
    (x - 3)3 = (³√7)3
    ⇒ x3 - 3.x2.3 + 3.x.(3)2 - (3)3 = 7
    ⇒ x3 - 9x2 + 27x - 27 = 7
    ⇒ x3 - 9x2 + 27x - 34 = 0

    Correct Option: A

    x = ³√7 + 3
    ⇒ x - 3 = ³√7
    On cubing both sides ,
    (x - 3)3 = (³√7)3
    ⇒ x3 - 3.x2.3 + 3.x.(3)2 - (3)3 = 7
    ⇒ x3 - 9x2 + 27x - 27 = 7
    ⇒ x3 - 9x2 + 27x - 34 = 0



  1. If c +
    1
    = 3 , then the value of (c - 3)7 +
    1
    is
    cc7










  1. View Hint View Answer Discuss in Forum

    c +
    1
    = 3
    c

    ⇒ c - 3 = -
    1
    c

    ∴ (c - 3)7 +
    1
    = -
    1
    7 +
    1
    c7cc7

    Required answer = -
    1
    +
    1
    = 0
    c7c7

    Correct Option: B

    c +
    1
    = 3
    c

    ⇒ c - 3 = -
    1
    c

    ∴ (c - 3)7 +
    1
    = -
    1
    7 +
    1
    c7cc7

    Required answer = -
    1
    +
    1
    = 0
    c7c7