Page 96 - Mathematics Class - XI
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Case-Study Based Questions
                                    Case-Study Based Questions


          A function is said to be a rational function, if  fx () =  gx()  , where g (x) and h(x) are polynomial functions such
          that h (x) ≠ 0.                                   hx ()
                                          gx
                               gx     lim( )     ga
                                                  ()
                                ()
          Then,  lim( )limfx           x  a
                                          hx
                 x  a      x  a  hx   lim( )     ha
                                ()
                                                  ()
                                      x  a
          However, if h(a) = 0, then there are two cases arise
            (i)  g (a) ≠ 0               (ii)  g (a) = 0
          In the first case, we say that the limit does not exist.
          In the second case, we can find limit.
          Based upon the above data, answer the following questions.

                       x    x     1
                       10
                            5
             1.  lim               is equal to
                 x  1    x  1
                                                1
                 (a)  1                  (b)  −                (c)  2                   (d)   3
                      2                         2                                            2
                           2
             2.  lim  (x  1 )   3 x  2   is equal to
                         4
                 x  1  (x  1 ) 2
                 (a)  7                  (b)  6                (c)   4                  (d)  3
                      4                       5                      7                       4


                              Assertion-Reason Based Questions
                              Assertion-Reason Based Questions
           Directions for Questions 1 to 2:  In each of the questions given below, there are two statements marked as
           Assertion (A) and Reason (R). Mark your answer as per the codes provided below:
             (a)  Both A and R are true and R is the correct explanation of A.
             (b)  Both A and R are true but R is not the correct explanation of A.

             (c)  A is true but R is false.      (d)  A is false but R is true.

                                      cos x  2  1
             Q. 1.  Assertion (A) :  lim        is equal to 4
                                  x 0  cos x  1
                                      tan x
                  Reason (R)    :  lim      1
                                  x 0   x
                                      sin(     ) x
             Q. 2.  Assertion (A) :  lim         is equal to p
                                        (
                                  x           ) x
                  Reason (R)    :  lim cos x  is equal to   1
                                  x 0      x          p


                                                         Answers

           Case-Study Based Questions:           1. (b)      2.  (a)
           Assertion-Reason Based Questions:  1. (b)          2.  (d)



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