sample examination questions for engineering mathematics

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  • 7/27/2019 Sample Examination Questions for Engineering Mathematics

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    Sample Examination Questions for Engineering Mathematics

    Chapter 6

    1. Differentiate each of the following with respect to the variable in each case.

    (i)

    6

    3 7 2

    5 9 263

    x

    y x xx

    = + + + (ii)2

    2 lny x x

    =

    (iii)24

    sin5

    xey

    x

    = (iv) 2 31 5 4y x x= +

    Solutions

    1. (i) 4 2 515 7 4 9x x x + (ii)2

    2 ln 1x

    (iii)( ) ( )

    ( )

    2

    2

    4 2sin 5 5cos 5

    sin 5

    xe x x

    x

    + (iv)

    [ ]2 3

    5 6

    1 5 4

    x x

    x x

    +

    2. If ( )cosh /y a x a c= + , where a and c are constants, show that22

    2

    d 1 d1

    d d

    y y

    x a x

    = +

    Solution

    2. Use a hyperbolic identity ( ) ( )2 2cosh sinh 1t t = .

    3. A curve is given, parametrically, by

    2sin , cos

    2 2

    t tx t y t

    = =

    Find thex- andy coordinates of the pointPwhich corresponds to the parameter 1t=

    and find the value ofd

    d

    y

    xatP.

    Solution

    3. ( )0, 1P= , 22

    Chapter 8

    4. Find the integrals:

    (i) ( )2

    3

    1

    4 1x x dx

    + (ii)/4

    0

    cos 24

    t dt

    (iii) 2 1

    x dxx +

    (iv) ( )sin d (v) ( ) ( )3

    1 2dx

    x x+ (vi)1/2

    2

    0

    1

    1dx

    x

    Solutions

    4. (i)1

    162

    (ii)1

    2(iii) ( )2

    1ln 1

    2x C+ +

    (iv) ( ) ( )cos sin C + + (v)2

    ln1

    xC

    x

    +

    +(vi)

    6

    5. Evaluate each of the following definite integrals.

  • 7/27/2019 Sample Examination Questions for Engineering Mathematics

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    (a) ( ) ( )3

    3

    0

    8cos sinx x dx

    (b)( )4

    1

    ln xdx

    x

    Solution

    5. (a)

    15

    8 (b) ( )4 ln 4 1 Chapter 7

    6. Determine the dimensions of the rectangle of largest area with a fixed perimeter of

    20 feet.

    7. You are to construct an open (no top) rectangular box with a square base. Material

    for the base costs 30 cents/in.2 and material for the sides costs 10 cents/in.2. If the

    boxs volume is required to be 12 in.3, what dimensions will result in the least

    expensive box?

    Solutions

    6. A square of edge 5 feet.7. 2 in. by 3in.

    Chapter 9

    8. Find the area of the region bounded by the curve23y x x= and thex axis.

    9. R is the region bounded by the curves ( )3 siny x= , ( )siny x= , 0x = andx = . Find the area ofR.

    10. Using Simpsons rule with 4 strips, find an approximate value of the integral

    2

    1

    0

    xe dx .

    11. Write down the Trapezoidal Rule approximation 3T for ( )4

    1

    cos /x x dx . Leaveyour answer expressed as a sum involving cosines.

    [ 3T in this question means consider 3 intervals].

    12. Approximate

    2

    2

    01

    xdx

    x+ using the Trapezoidal Rule with 4n = subintervals.

    13. Find the area under the graph of lny x= between 1x = and 3x = .Solutions

    8. 9/2

    9. 3 4 10. ( )1.464 3dp

    11. ( ) ( ) ( )( ) ( )1

    cos 2 2cos / 2 3cos / 3 4cos / 42

    + + +

    12. ( )0.78077 5dp

    13. ( )ln 27 2

  • 7/27/2019 Sample Examination Questions for Engineering Mathematics

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    Chapter 10

    14. Given that 1 4 2z j= + , 2 3z j= find (i) 1 23 2z z+ (ii) 1 2z z

    15. Given 1 2z j= + , 2 3 4z j= , find (a) 1 2z z (b) Both values of 1z16. Find the four solutions to the equation

    4

    2 2 3z j= and display them on an Argand diagram.

    17. Determine all complex 3rd roots of8i .

    18. Determine all complex numberszsuch that 5 32z = .

    Solutions

    14. (i) 18 4j+ (ii) 14 2j+

    15. (a) 10 5j (b) ( )1/ 45 13.28 and ( )1/ 45 193.2816. ( )1 2 60z = , ( ) ( ) ( )2 3 42 150 , 2 240 and 2 330z z z= = =

    17. ( )1 2 30z = , ( )2 2 150z = and ( )3 2 270z = 18. ( )1 2 36z = , ( )2 2 108z = , ( )3 2 180z = , ( )4 2 252z = and ( )5 2 324z =

    Chapter 11

    19. Let1 2

    3 4

    =

    A and

    5 6

    7 8

    =

    B . Determine (i) ( ) ( ) +A B A B (ii) 2 2A B

    20. Given the matrix

    3 2 61

    2 6 37

    6 3 2

    =

    A

    (a) Compute 2A and 3A .

    (b) Based on these results, determine the matrices 1A and 2004A .

    21. Let A, B and C be matrices defined by

    1 11 0 1

    1 2 1 1 1 01 1 1 , ,

    0 1 2 1 2 31 2 3

    0 1

    = = =

    A B C

    Which of the following are defined?2, , , , , ,T T+ A AB B C A B CB BC A

    Compute those matrices which are defined.

    22. Find the determinant of the matrix

    0 1 5

    3 6 9

    2 6 1

    =

    A .

    23. The mesh equations of a circuit are given by:

    1 2 3

    1 2 3

    1 2 3

    3 2 13

    4 4 3 3

    5 2 13

    i i i

    i i i

    i i i

    + + =+ =+ + =

    Determine the values of 1 2 3, andi i i .

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    Solutions

    19. (i)4 5

    164 5

    (ii)

    15 174

    19 21

    20. (a) 2 =A I and3

    3 2 612 6 3

    76 3 2

    =

    A (b) 1 =A A and 2004 =A I

    21.

    1 1 1

    0 1 2

    1 1 3

    T

    =

    A ,0 2

    1 1

    =

    CB ,2

    0 2 4

    3 3 3

    6 8 10

    =

    A . AB, +B C , A B and

    tBC is not valid.

    22. ( )det 165=A

    23. 1 1i = , 2 2i = and 3 3i =