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Single Correct Choice Type                            Jai Baba Ki9
                                                                 x      y     z
          44. Equation of the plane containing the straight line    =     =     and perpendicular to the plane
                                                                 2      3     4
                                         x    y    z      x    y   z
              containing the straight lines  =   =   and    =    =   is
                                          3   4    2      4    2   3
               (A) x + 2y − 2z = 0.                             (B) 3x + 2y − 2z = 0.
               (C) x − 2y + z = 0.                              (D) 5x + 2y − 4z = 0.


                                                                                                    [JEE 2010]

                                                                                                ˆ
                                                                                                         ˆ
                                                                                                              ˆ
                                                                                 ˆ
                                                                                     ˆ ˆ ˆ
          45. Let P, Q, R and S be the points on the plane with position vectors −2i − j, 4i, 3i + 3j and −3i + 2j
              respectively. The quadrilateral PQRS must be a
               (A) parallelogram, which is neither a rhombus nor a rectangle.
               (B) square.
               (C) rectangle, but not a square.
               (D) rhombus, but not a square.

                                                                                                    [JEE 2010]

          46. The number of 3 × 3 matrices A whose entries are either 0 or 1 and for which the system
                                                                
                                                           x       1
                                                                
                                                        A y = 0
                                                           z       0
              has exactly two distinct solutions, is

                                             9
               (A) 0.                  (B) 2 − 1.               (C) 168.                (D) 2.
                                                                                                    [JEE 2010]

                               1  Z  x  t ln (1 + t)
          47. The value of lim                   dt is
                           x→0 x 3      t + 4
                                         4
                                   0
                                            1                        1                        1
               (A) 0.                  (B)    .                 (C)    .                (D)     .
                                            12                      24                       64
                                                                                                    [JEE 2010]


          48. Let f, g and h be real-valued functions defined on the interval [0, 1] by
                                                                                    2 x
                              f(x) = e x 2  + e −x 2 , g(x) = xe x 2  + e −x 2  and h(x) = x e  2  + e −x 2 .
              If a, b and c denote, respectively, the absolute maximum of f, g and h on [0, 1], then
               (A) a = b and c 6= b.   (B) a = c and a 6= b.    (C) a 6= b and c 6= b.  (D) a = b = c.


                                                                                                    [JEE 2010]

                                   4
                             Z  1  x (1 − x) 4
          49. The value(s) of                dx is(are)
                                   1 + x 2
                               0
                   22                        2                                               71    3π
               (A)    − π.             (B)      .               (C) 0.                  (D)     −    .
                    7                       105                                              15    2
                                                                                                    [JEE 2010]
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