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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 1of 6

    [WINTER, 2013] SCHEME OF EVALUATION

    PROGRAM BCA REVISED 2012

    SEMESTER ISUBJECT CODE &

    NAME

    BCA 1030- BASIC MATHEMATICS

    CREDIT 4

    BK ID B0947

    MAX. MARKS 60

    Q.No Question and Scheme of Evaluation Unit/Page No.

    Marks TotaMark

    1(i) LetA = {1, 2, 3, 4, 5, 6}and B = {2, 4, 6, 8}. Find A B and

    B A.

    (ii) In a group of 50people, 35speak Hindi, 25speak both English

    and Hindi and all the people speak at least one of the two languages.

    How many people speak only English and not Hindi ? How many

    people speak English?

    A(i) We have A B = {1, 3, 5}, as the only elements of A which do not

    belong to B are 1, 3 and 5. Similarly, B A = {8}.

    We note that A B B A

    (ii) Let H denote the set of people speaking Hindi and E the set of people

    speaking English. We are given that n(H E) = 50, n(H) = 35,

    n(HE) = 25. Now

    n(H E) = n(H) + n(E H).

    So 50 = 35 + n(E H), i.e. , n(E H) = 15.

    Thus, the number of people who speak only English but not Hindi is

    15.

    Also, n(H E) = n(H) + n(E) n(H E) implies50 = 35 + n(E) 25,

    which gives n(E) = 40.

    Hence, the number of people who speak English is 40.

    2

    8

    10

    2 (i) Express 792in radians and (7/12)c in degrees

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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 2of 6

    (ii) Prove that

    cos

    sin1

    sin1

    cos

    1sectan

    1sectan

    A

    (i)

    radians180/xx

    cradians 5/22180/)792(792

    10512

    1807)

    12

    7( c

    (ii)

    1sectan

    1sectanLHS

    22 sectan1

    1sectan

    tansecsectan 22

    1sectan

    tansectansecsectan

    1sectan

    tansec1sectan

    cos

    1sin

    cos

    1

    cos

    sinsectan

    ..(1)

    Now

    sin1cos

    sin1sin1

    cos

    sin1

    sin1cos

    sin1 2

    22

    22

    sin1cos

    1cossin

    sin1

    cos

    sin1cos

    cos2

    (2)

    From (1)and (2)the result follows

    2

    8

    10

    3 (i) Define continuity of a point

    (ii) Test the continuity of the function f where f is defined by

    27

    2|2|

    2

    xif

    xifx

    x

    xf

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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 3of 6

    A (i)Let f be a function of a real variable defined in an open interval containing

    a. Then f is continuous at a if afxfItax

    (ii)Whenx < 2, |x

    2|is negative. So|x

    2| =

    (x

    2)

    12x

    2xxf

    Whenx > 2, |x2|is positive. So |x2| = x 2, 12x

    2xxf

    f(2) = 7. Thus

    21

    27

    21

    xif

    xif

    xif

    xf

    As in the previous worked example,fis continuous for all a < 2and all a >

    2.

    11ItxfIt2x2x

    11ItxfIt2x2x

    As xfIt,xfItxfIt2x2x2x

    does not exist. So f is continuous at all

    points except 2.

    2

    8

    10

    4Solve

    4xy

    2xy

    dx

    dy

    A

    The given equation is4xy

    2xy

    dx

    dy

    [this is where

    ]b

    b

    a

    a

    --------- (1)

    Puttingx = X + h, y = Y + k(h, k being constants)

    So that dx = dX, dy = dY,(1) becomes

    )4hk(XY

    )2hk(XY

    dX

    dY

    ---------

    (2)

    Put k + h2 = 0and kh4 = 0,

    So that, h =1, k = 3.

    Therefore (2) becomes,XY

    XY

    dX

    dY

    ..(3)

    Which is homogeneous in X and Y.

    10 10

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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 4of 6

    Put Y = vX,thendx

    dvXv

    dX

    dY

    Therefore (3) becomes,1v

    1v

    dX

    dvXv

    Or 1

    21

    1

    1 2

    v

    vvv

    v

    v

    dX

    dvX

    X

    dXdv

    vv

    v

    221

    1

    Integrating both the sides

    c

    X

    dXdv

    vv21

    v22

    2

    1

    2

    Or

    cXlogvv21log2

    1 2

    Or

    c2XlogX

    Y

    X

    Y21log 2

    2

    2

    Or log (X2+ 2XY Y2) = 2c

    Or X2+ 2XY y2 = e 2c= c

    PuttingX = xh = x + 1,and Y = yk = y- 3,equation (4) becomes,

    c3y3y1x21x 22

    Which is the required solution.

    5 A bag contains two red balls, three blue balls and five green balls.

    Three balls are drawn at random. Find the probability that

    a) the three balls are of different colours

    b) two balls are of the same colour

    c) all the three are of the same colour.

    A Let E denote the given event..

    a) We can choose one red ball in C (2, 1)ways, etc. So

    3,10C1,5C1,3C1,2C

    EP

    4

    13.2.1.

    8.9.10

    5.3.2

    10 10

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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 5of 6

    b) Let E1, E2, E3denote the events that two balls among the three are red,

    blue and green respectively.

    15

    13.2.1.

    8.9.10

    8.1

    3,10C

    1,8C2,2CEP 1

    Similarly

    407

    3.2.1.8.9.10

    7.3

    3,10C

    1,7C2,3CEP 2

    125

    3.2.1.8.9.10

    5.

    2.1

    4.5

    3,10C

    1,5C2,5CEP 3

    So P(E) = P(E1) + P(E2) + P(E3)12

    5

    40

    7

    15

    1

    120

    50218

    120

    79

    c) As there are only two red balls, the chosen three balls are of the same

    colour only if they are all blue or green.

    Let E1, E2 denote the events that the three balls are blue and green

    respectively.

    1201

    3.2.1.8.9.10

    1

    3,10C

    3,3CEP 1

    121

    3.2.1.8.9.10

    3.2.1.

    2.1

    4.5

    3,10C

    3,5CEP 2

    SoP(E) = P(E1) + P(E2)12

    1

    120

    1

    120

    101

    120

    11

    6 Solve: 2x + 3y + 4z = 20, x + y + 2z = 9, 3x + 2y + z = 10

    AIn this example,

    1023

    911

    2032

    1103

    291

    4202

    1210

    219

    4320

    123

    211

    432

    321

    = 2(1 4) 3 (1 6) + 4(2 3) = 5

    1= 20(1 4) 3(9 20) + 4 (18 10) = 5

    2= 2(9 20) 20(1 6) + 4 (10 27) = 10

    3= 2(10 18) 3 (10 27) + 20(2 3) = 15

    Hence

    10 10

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    F-37 ver.1 dated 20-05-2013-Scheme of Evaluation (SoE) Page 6of 6

    .3z,2y,1x 321

    *A-Answer

    NotePlease provide keywords, short answer, specific terms, and specific examples (wherever necessary)

    ***********