sample examination questions for engineering mathematics
TRANSCRIPT
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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.
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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
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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 =