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2Jai Baba Ki             ISC Mathematics – Class XII by Gupta–Bansal
                                      π π

           2. Let f 1 : R → R, f 2 : − ,     → R, f 3 : −1, e π/2  − 2 → R and f 4 : R → R be functions defined
                                      2 2
              by
                                √

                (i) f 1 (x) = sin  1 − e −x 2  ,
                               | sin x|
                            
                                       if x 6= 0
                                 −1
                                                                                             −1
               (ii) f 2 (x) =  tan x             , where the inverse trigonometric function tan x assumes values
                            
                                  1     if x = 0
                            
                         π π

                   in − ,      ,
                         2 2
               (iii) f 3 (x) = [sin (log (x + 2))], where for t ∈ R, [t] denotes the greatest integer less than or equal
                                    e
                   to t,
                            
                                      1
                                2
                             x sin      if x 6= 0
                            
                                      x
               (iv) f 4 (x) =                     .
                            
                                  0      if x = 0
                            
                              List-I                                        List-II
                (P)   The function f 1 is              (1)  NOT continuous at x = 0


                (Q)   The function f 2 is              (2)  continuous at x = 0 and NOT differentiable at

                                                            x = 0

                (R)   The function f 3 is              (3)  differentiable at x = 0 and its derivative is NOT

                                                            continuous at x = 0

                (S)   The function f 4 is              (4)  differentiable at x = 0 and its derivative is

                                                            continuous at x = 0




              The correct option is:

               (A) P → 2; Q → 3; R → 1; S → 4.
               (B) P → 4; Q → 1; R → 2; S → 3.
               (C) P → 4; Q → 2; R → 1; S → 3.

               (D) P → 2; Q → 1; R → 4; S → 3.
                                                                                                    [JEE 2018]
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