Code: A-35/C-35/T-35                                                                     Subject: MATHEMATICS-II

Time: 3 Hours                                                  June 2006                                       Max. Marks: 100

 

NOTE: There are 9 Questions in all.

·      Question 1 is compulsory and carries 20 marks. Answer to Q. 1. must be written in the space provided for it in the answer book supplied and nowhere else.

·      Out of the remaining EIGHT Questions answer any FIVE Questions. Each question carries 16 marks.

·      Any required data not explicitly given, may be suitably assumed and stated.

 

 

Q.1       Choose the correct or best alternative in the following:                                         (2x10)

       

a.       Which of the following is an entire function     

 

                   (A)                                           (B)  

(C)                                              (D)                                                                                                                         

       

             b.   Let .  Then which of the following statements is not correct.

 

(A)    f is differentiable at z = 0.              (B)  f is differentiable at z 0.

(C)  f is not analytic at z = 0.                (D)  f is not analytic at z  0.

            

             c.   The image of a square under the transformation  is  

                  

(A)    a square                                       (B)  a circle

(C)  the upper half plane                      (D)  the right half plane

 

             d.   The value of  is

 

(A)                                              (B)  0

(C)                                              (D) 

 

             e.   The value of line integral , where C is the segment of the parabola  from (0, 0) to (1, 1) is    

                  

(A)                                                   (B)  0

(C)                                                 (D) 

             f.    The directional derivative of  at the point  in the direction of  is   

 

(A)                                                (B) 

(C)  0                                                  (D)  1

 

             g.   The unit normal to the surface  at the point  is    

 

(A)                                        (B) 

(C)                                     (D)  None of the above

 

 

             h.   Which of the following probability mass functions can define a probability distribution

 

(A)           (B)

(C)           (D)

 

             i.    The expected value of a random variable X is 3 and its variance is 2.  Then the variance of 2X + 5 is

 

(A)   8                                                  (B) 9

(C) 10                                                 (D) 11

 

             j.    The equation  is    

 

(A)  Elliptic                                          (B)  Parabolic

(C)  Hyperbolic                                   (D) None of the above

 

 

Answer any FIVE Questions out of EIGHT Questions.

Each question carries 16 marks.

 

  Q.2     a.   Compute the limit .                                                  (8)

       

             b.   Show that cosh , where .                                                            (8)

 

  Q.3     a.   Evaluate the integral , by contour integration.                              (10)

 

             b.   Evaluate , where C is the circle  traversed counter clockwise.                                                                       (6)                                                             

 

  Q.4     a.   Show that the function  in polar coordinates   (r, ) is harmonic.  Find the corresponding harmonic conjugate function and construct the analytic function f (z) = u + iv such that f(1) = 1.                                                        (8)

 

             b.   Find the Fractional Linear Transformation which maps the unit disc  onto the right half plane .                                         (8)

 

  Q.5     a.   A thin rectangular homogenous thermally conducting plate lies in the xy-plane defined by  .  The edge y = 0 is held at the temperature x (x – 1), while the remaining edges are held at temperature .  The other faces are insulated and no internal sources and sinks are present.  Find the steady state temperature inside the plate.                                                          (10)

       

             b.   It has been claimed that in 60% of all solar heat installations, the utility bill is reduced by at least one third.  Accordingly what are the probabilities that the utility bill will be reduced by at least one-third in  

(i)                  four of five installations,

(ii)                at least four of five installations.                                    (6)

 

  Q.6     a.   Let the probability density function of a random variable x be given by

                   Find the corresponding cumulative distribution function and determine the probabilities that the random variable x will take a value

                   (i)  greater than                             (ii)  between 0 and .                         (8)

 

             b.   Consider the heat flow in a thin rod of length l, l.  The ends x = 0 and x = l are insulated.  The rod was initially at temperature f (x) = x.  By the method of Separation of Variables, find the temperature distribution      u (x, t) in the rod, where u (x, t) is governed by the partial differential equation .                                                                                                                         (8)          

         


 

  Q.7     a.   If the amount of a cosmic radiation to which a person is exposed while flying by jet across India is a random variable having the normal distribution with  mrem and  mrem, find the probability that the amount of cosmic radiation to which a person will be exposed on such a flight is between 4.00 and 5.00 mrem.                                                 

                   Given that F(1.10) = 0.8643, F(-0.59) = 0.2776, where F is the distribution function of the standard normal distribution.                                          (4)

 

             b.   Let the probabilities that there are 0, 1, 2 and 3 power failures in a certain city during the month of July be respectively 0.4, 0.3, 0.2 and 0.1. Find the mean and variance of the number of  power failures during the month of July in the city.                                                                                    (4)

 

             c.   Show that  is a conservative force field.  Find its scalar potential and the work done in moving an object in this field from (1, -2, 1) to (3, 1, 4).                    (8)

       

  Q.8     a.   Find the work done in moving the particle in the force field  along the space curve ,  from x = 0 to x = 2.                                                       (8)

 

             b.   Evaluate , where , S is the surface of the plane x + y + z = 1 in the first octant and  is unit outward normal to the surface S.                                                   (8)

 

  Q.9     a.   Verify the divergence theorem for  on the surface S of the sphere .                                                                                          (8)

 

             b.   Verify Stokes theorem for , on the surface S of the sphere  above the xy-plane.                             (8)