SCHOOL OF ELECTRICAL & COMMUNICATION
DEPARTMENT OF ECE
                                                                     VTU R 2015
                                                                  Assignment – II
                                                                   B.Tech. - ECE
                                           Course Category: Programme Core
                    Course Code/Course Title: 1151EC101 /Mathematics for E & C                           Max. Marks: 5
                                                    Semester: Even
                                                                                                  Date of Submission:18-04-2018
                                                         Achievable Course Outcomes
    CO3: Examine the random experiments specified by two random variables and study the Distribution of
    their distributions
    CO4: Determine covariance and spectral density of stationary random processes
    CO5 : Derive numerical methods for various mathematical Operations and tasks, such as interpolation,
    differentiation, integration, the solution of linear and nonlinear equations, and the solution of differential
    equations.                                                                                        -K3 Level
 S.                                                                                                              Course
                            Assignment Topics/Questions-Written Assignment                             Marks                 Level
No.                                                                                                             Outcome
                 a) The joint distribution of X and Y is given by
                            x+ y
             f ( x, y ) =        , x = 1, 2,3...; y = 1, 2,3... Find the marginal distribution.
                             21
1                b) Apply Gauss-seidel method to solve the equations                                            CO3, CO5       K3
                                                                                                          5
                       20x+y-2z=17: 3x+20y-z=-18: 2x-3y+20z=25.
                 a) Suppose the point probability density functions is given by
                                  �6
                                  � ( x + y ),0 �x �1, 0 �y �1
                                           2
                     f ( x, y ) = �5
                                  �
                                  �0, otherwise
2                                                                                         1       3       5     CO3, CO5       K3
         Obtain the marginal pdf of X and that of Y and hence find P [ �y � ]
                                                                                          4       4
         .
                 b) Find a positive root of 3x- log 10 X =6, using fixed point iteration
                    method.
3                a) Let X and Y have joint probability density                                            5     CO3, CO5       K3
             f ( x, y ) = 2 0 < x < y < 1 Find the marginal distribution of f also find the
         conditional density function of y given X=x
    CC                                                                                                                   HOD
                                                 SCHOOL OF ELECTRICAL & COMMUNICATION
                                                           DEPARTMENT OF ECE
                                                               VTU R 2015
                  b) Find the smallest positive root of the equation x         = sin x
                      correct to 3 decimal places using Newton-Raphson method
                  a) The joint pdf of the random variable ( x , y ) is given by
                                             2   2
                      f ( x, y ) = k x y e - ( x + y ) , x > 0, y > 0.
4                    Find the value of k and prove that X and Y are independent.            5   CO3, CO5     K3
                  b) Solve by Gauss-seidel iterative procedure the system 8x-3y-2z=20:
                     6x+3y+12z=35: 4x+11y-z=33
                                                         �2
                                                         � (2 x + 3 y ), 0 �x �1, 0 �y �1
                  a) Show that the function f ( x, y ) = �5
                                                         �
                                                         �0,otherwise
5        Is a joint probability density function of X and Y .                               5   CO3, CO5     K3
                  b) Find a real root of the equation x3+x2-1=0 by iteration method.
                  a) If the joint probability density function of x and Y is given by
                                   �1
                                   � (6 - x - y ), 0 < x < 2, 2 < y < 4
                      f ( x, y ) = �8                                   Find
                                   �
                                   �0             otherwise
6        (i )          P( x < 1 and y < 3)
                                                                                            5   CO3, CO5     K3
         (ii )         P( x < 1/ y < 3)
         (iii )        P ( x + y < 3).
              b) Using Newton’s method, find the real root of x log 10 X=1.2 correct
                    to five decimal places
7             a) The joint density function of the random variable X and Y is               5   CO3, CO5     K3
                    given by
                      �8 xy ) 0 < x < 1, 0 < y < x             1     1
         f ( x, y ) = �                            Find P ( y < / x < ) . Also find the
                      �0             otherwise                 8     2
         conditional density function f ( y / x ).
                  b) Apply Gauss elimination method to find the solution of the
                     following system :
    CC                                                                                                 HOD
                                     SCHOOL OF ELECTRICAL & COMMUNICATION
                                               DEPARTMENT OF ECE
                                                       VTU R 2015
         2x+3y-z=5: 4x+4y-3z=3: 2x-3y+2z=2.
            a) Two random variables X and Y have the joint density function
                              (2 - x - y ), 0 < x < 1, 0 < y < 1
                              �
                 f ( x, y ) = �
                              0
                              �              otherwise
                                            -1
                Show that cor ( x, y ) =       .
8                                          144                                          5   CO3, CO5     K3
            b) Find an iterative formula to find      , where N is a positive number
                and hence find
            a) Suppose that the 2D random variables ( X , Y ) has the joint
               probability function
                             �x + y, 0 < x < 1,0 < y < 1
                f ( x, y ) = �
                             �0            otherwise
                Obtain the correlation coefficient between X and Y and check
9                                                                                       5   CO3, CO5     K3
                whether X and Y are independent.
            b) Solve the following system of equations by Gauss-Jacobi method:
         27x+6y-z=85:x+y+54z=110: 6x+15y+2z=35.
            a) Let X , Y and Z be uncorrelated r.v. with zero means and
               standard deviation 5,12 and 9 respectively. If U = X + Y and
               V = Y + Z ,find the correlation coefficient between U and V .
10                                                                                      5   CO3, CO5     K3
            b) Apply Gauss-Jacobi method to find the solution of the following
               system:    10x+y+z=12: 2x+10y+z=13: x+y+5z=7
            a) The two regression lines are 4 x - 5 y + 33 = 0 and 20 x - 9 y = 107 ,
                variance of x = 25 .Find the means of x and y .
            b) Find the negative root of x2 + 4sinx = 0 by Newton’s
11             Raphson method                                                           5   CO3, CO5     K3
    CC                                                                                             HOD
                             SCHOOL OF ELECTRICAL & COMMUNICATION
                                       DEPARTMENT OF ECE
                                                VTU R 2015
      a) The two regression lines are 8 x - 10 y + 66 = 0 and
          40 x - 18 y - 214 = 0 , variance of x = 9 .Find the means of x and y
         ,correlation coefficient between x and y .
      b) Solve the following system of equation by Gauss - seidel
12                                                                               5   CO3, CO5     K3
          method
      a) Consider the random process
          where      is uniformly Distributed in the interval
          to     check whether              is stationary or not? Find
13                                                                               5   CO3, CO5     K3
          the first and second moments of the process
      b) Solve the following system of equations by Gauss-Seidel
          method:
14                                                                               5   CO3, CO5     K3
      a) Show that if the process
            is SSS, where ‘a’ and ‘b’ are independent random
                     variable then they are normal.
      b) Solve by Gauss elimination method:
 CC                                                                                         HOD
                             SCHOOL OF ELECTRICAL & COMMUNICATION
                                       DEPARTMENT OF ECE
                                              VTU R 2015
         a) The process            whose probability distribution
            under certain condition is
      given by
15                                                                        5   CO3, CO4     K3
      Show that it is “not stationary”.
         b) Use Newton’s method to find a real root of the equation   +
            x -1=0
 CC                                                                                  HOD
                             SCHOOL OF ELECTRICAL & COMMUNICATION
                                       DEPARTMENT OF ECE
                                           VTU R 2015
      a) Consider the random process
                                        where A and      are
          Independent variables. A is a random variable with
          mean 0 and variance 1.       is uniformly distributed in
16
                     Find mean and auto correlation and Hence         5                K3
          show that          is WSS.                                      CO3, CO5
      b) Using Lagrange’s interpolation formula, find      from the
          following table.
              3               7             9           10
              168             120           72          63
      a) Show that the poisson process is a Markov process.
      b) Solve the following system of equations by Gauss-Seidel
         method:
17                                                                    5   CO3, CO5     K3
      a) A customer arrive at a certain in accordance with a
         poisson process with a mean rate of 2 per min.
      b) Find the probability that the interval between 2
         consecutive arrivals is a)more than 1 min b)between
18       1 min and 2 min c) 4 min or less                             5   CO3, CO5     K3
      c) Use Newton’s method to find a real root of the equation
      + x - 1 = 0.
 CC                                                                              HOD
                               SCHOOL OF ELECTRICAL & COMMUNICATION
                                         DEPARTMENT OF ECE
                                               VTU R 2015
       a) If the tpm of a markov chain is                   find the
19          steady state distribution of the chain.                        5   CO3, CO4     K3
       b) Solve by Gauss elimination method:
       a) The transition probability matrix of the markov
            chain       } n=1,2,.. having 3 states 1,2 and 3 is
                                      and the initial distribution is
                                      Find
20                                                                         5   CO3, CO4     K3
      (i)            =3 and (ii)
       b) Using Lagrange’s interpolation formula, find          from the
            following table.
               3                7               9             10
               168              120             72            63
21     a) Consider the random process                                      5   CO3, CO4     K3
                                             where A and      are
            Independent variables. A is a random variable with
            mean 0 and variance 1.       is uniformly distributed in
 CC                                                                                   HOD
                                    SCHOOL OF ELECTRICAL & COMMUNICATION
                                              DEPARTMENT OF ECE
                                                         VTU R 2015
                           Find mean and auto correlation and Hence
          show that                  is WSS.
      b) Using Lagrange’s interpolation formula, find                         from the
          following table.
                3                     7                    9               10
                168                   120                  72              63
      a) The two regression lines are 8 x - 10 y + 66 = 0 and
          40 x - 18 y - 214 = 0 , variance of x = 9 .Find the means of x and y
         ,correlation coefficient between x and y .
      b) Solve the following system of equation by Gauss - seidel
22                                                                                         5   CO3, CO5     K3
          method
      c) The joint distribution of X and Y is given by
                     x+ y
      f ( x, y ) =        , x = 1, 2,3...; y = 1, 2,3...
                      21                                 Find the marginal distribution.
23                                                                                         5   CO3, CO5     K3
      d) Apply Gauss-seidel method to solve the equations
      20x+y-2z=17: 3x+20y-z=-18: 2x-3y+20z=25.
           a) Suppose the point probability density functions is given by
                   �6
                   � ( x + y ), 0 �x �1, 0 �y �1
                            2
      f ( x, y ) = �5
                   �
                   �0, otherwise
      Obtain the marginal pdf of X and that of Y and hence find
24                                                                                         5   CO3, CO5     K3
              1    3
           P [ �y � ]
              4    4 .
          b) Find a positive root of 3x- log 10 X =6, using fixed point
             iteration method.
 CC                                                                                                   HOD
                                  SCHOOL OF ELECTRICAL & COMMUNICATION
                                            DEPARTMENT OF ECE
                                                     VTU R 2015
                 a) Let X and Y have joint probability density
      f ( x, y ) = 2 0 < x < y < 1 Find the marginal distribution of f also find the
      conditional density function of y given X=x
25                                                                                     5   CO3, CO4     K3
             b) Find the smallest positive root of the equation x = sin x
                correct to 3 decimal places using Newton-Raphson method
 CC                                                                                               HOD