PT-1(JP) 28-04-2013

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    SOLJPPT12804913 - 1

    PAPER-1

    PART-I (Physics)

    1. Plane surface .........................................

    Sol . (3)

    x

    1

    x

    1

    =

    1

    2

    3

    300

    11

    300

    1.

    2

    1

    x

    2 x = 1200 cm = 12m

    so 3m

    2. A plane mirror is .........................................Sol . (5)

    Let 1

    , 2

    and 3

    be the image formed by :(i) Refraction from ABC

    (ii) Reflection from DEF and(iii) Again refraction from ABC

    then B1= 5n = 7.5 cm

    Now E1= 7.5 + 2.5 = 10 cm

    Now B2= 10 + 2.5 = 12.5 cm

    BI3=

    n

    5.12=

    5.1

    5.12= 8.33 cm.

    3. (1)

    4.

    Sol . (5)

    Initial velocity of centre of mass of (A + B) system is

    ucm

    =3

    8522001 = 10m/s upwards

    maximum height attained by centre of mass aboveits initial position is

    H =g2

    u2

    cm =102

    100

    = 5 metres

    Ans . 5 m

    5.

    Sol . (1)

    Ans. 1

    Vefflux

    = gh2

    time of fall t =g

    2)h4(

    HINTS & SOLUTIONS

    DATE : 28-04-2013

    COURSE : VIJETA (JP)

    PART TEST-1 (PT-1)

    TARGET : JEE (MAIN+ADVANCED)-2014

    x = Veffloy

    t = )h4(h2

    the roots of x are (0,4) and the maximum of x is at h = 2.The permitted value of h is 0 to 1 clearly h = 1 will give themaximum value of x is this interval.

    Al it er : If the column of water itself were from ground upto aheight of 4m, h = 2m would give the maximum range x.Farther the hole is from this midpoint, lower the range. Herethe nearest point possible to this midpoint is the base of the

    container. Hence h = 1m.

    6. 7

    7. 2

    8. In the given .........................................

    Sol . (6)

    for lens :20

    1

    30

    1

    v

    1

    v = 60 cm

    height of image formed by mirror is

    30

    4

    90

    = 1.2 cm

    9. In the figure shown .........................................Sol . (4)

    The image will move as shown in the figure. It is very clear fromthe figure that the required velocity is20 m/s So x = 4

    10. A loaded vertical .........................................So l. (2)

    KE =2

    1m2a2cos2 t

    PE =2

    1m2a2sin 2 t

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    KE PE =2

    1m2a2(cos2 t sin2 t)

    =2

    1m2a2cos2t

    Angular frequency = 2

    The time period =2

    T= 2 s

    11. 5

    12. 1.

    13. Figure shows a .........................................Sol. (25)

    mV = m2 OmV

    m = 2

    1 VG = VMG(1 + m

    2)

    = 10 4

    5=

    2

    25cm/sec

    14. 86

    15. A body of mass .........................................Sol. (10)

    =m

    K = 50

    8

    400

    2= 50

    V = 22 xAV2= (A2 x2)

    1 = 50

    100

    1A2

    A2=

    100

    1

    50

    1

    A2=100

    3

    A =10

    3

    100

    3

    x = 10

    16. 10

    PART-II (Chemistry)

    19. When a block of sodium was ................

    Sol. (8)

    bcc

    fcc

    fcc

    bcc

    V

    V

    d

    d (m - PV = const)

    20. How many of the above closed diagrams ...............Sol. 4

    a, c, d, e

    21. Number of rectangular faces .............Sol. (4)

    a b c = = 90, 120 90 4 faces

    22. An element A forms compounds ................Sol. (8)

    AB Can't be CsCl strucutre as 4 formula units in one unit cell.A

    2B Na

    2O type structure.

    AD2CaF

    2type structure.

    Coordination no. of A

    AB (ZnS) AB (NaCl) A C2 AD24 6 4 8

    3

    8443 = 8

    3

    8463 = 10.

    Since single digit so answer is 8.

    23. x g. of a cubic crystal of NaOH ..................Sol. (9)

    number of NaOH units dissolved = 3 1022 4

    moles of NaOH dissolved = 23

    22

    106

    1012

    = 0.2 molarity of NaOH = 0.2 mol/L molarity of Na+= 0.2 mol/L = y

    mass of NaOH = 0.2 40 = 8g = x

    Hence (x + 5y) = 8 + 5 0.2 = 9.

    24. Consider an element A. It crystallizes ...................

    Sol. (6)

    nearest

    next nearest

    farthest

    p =3x

    4

    q =x

    2

    r = 3x

    4 4

    3x x3 2x

    2= 6.

    25. Elements A, B and C form ................

    Sol. (6)Alternate corners = 4.Alternate edge centres = 4.

    A =8

    14 =

    2

    1

    B =4

    14 = 1

    C = 8

    1

    4 + 2

    1

    2 = 2

    3

    2

    1A , B,2

    3C AB2C3

    x = 1y = 2z = 3 x2+ y + z = 1 + 2 + 3

    = 6.

    26. 3

    27. 4

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    28. 9

    29. 13

    30. 11

    31. In hcp lattice, if a plane is .........

    Sol. (10).

    32. 'u'is the number of C3axis ..........Sol. 19

    PART-III (Mathematics)

    33. If equations ax2+ 2bx + c = 0......................Ans .2

    Sol. Adding all three equation, we get(a + 2b + c)(x2+ x + 1) = 02+ + 1 = 0

    +

    1= 1 3+ 3

    1

    = 2

    34. If the ratio of the roots..................................Ans .1Sol. ax2+ 2bx + c = 0 , k

    px2+ 2qx + r = 0 , k

    + k= a

    b2; k2 =

    a

    c

    + k= p

    q2; k2 =

    p

    r

    aq

    bp

    andar

    pc2

    2

    pr

    q

    ac

    b 22

    35. Find the number of integral ............................

    Ans .1

    Sol. log5

    15log

    3

    13 < 0

    2xlog3xlog 222 0

    log2

    2x 3 log2x + 2 = 0

    or (log2x 1) (log

    2x 2) = 0

    x = 2, 4

    only x = 4 satisfies the inequation x x 2 0The given system of inequalities has only one integral solution.

    36. Number of pair(s) of..................................

    An s. 1

    Sol. [(3, 2) only. Note that p

    2 for p > 2, p2

    1 = (p

    1) (p + 1)

    is even and divisible by 4 ]

    37. If =

    1sin1

    cos31sin

    1cos31

    .......................

    An s. 2Sol.= (3cos sin)2

    now 10 3cos sin 100 10

    5max

    = 2

    38. Number of real value ..................................Ans.1Sol. For non-trivial solution

    =a02

    2a1

    32a2

    = 0

    a3 2a 4 = 0 (a 2)(a2+ 2a + 2) = 0 a = 2

    39. If A = [aij]44

    such..................................Ans. 2Sol. |adj(adjA)| = |adjA|3

    = |A|9

    = (24)9

    b = 36 = 22.32

    40. The greatest common ..................................Ans . 6Sol. x2+ ax + b = (x + 1)(x + b) b + 1 = a

    x2+ bx + c = (x + 1)(x + c) c + 1 = b(x + 1)(x + b)(x + c) = x3 4x2+ x + 6

    1 + b + c = 4 2b = 4 b = 2, c = 3 and a = 1

    Alter : x3 4x2+ x + 6 = 0 = (x + 1)(x 2)(x 3)

    So quadratic will be x2 x 2 = 0 ; x2 2x 3 = 0

    After compairing

    b = 2, c = 3 and a = 1

    41. Ifclogalog2

    1

    bb

    ..................................

    Ans. 1

    Sol.clogalogblog

    2/1

    1

    1

    bbb

    +blogalogclog

    2/1

    1

    1

    ccc

    +

    clogblogalog2/1

    1

    1

    aaa

    =clogalogblog

    1

    bbb

    +blogalogclog

    1

    ccc

    +

    clogblogalog

    1

    aaa

    =abclog

    1

    b

    +abclog

    1

    c

    +abclog

    1

    a

    = logabc

    b + logabc c + logabc a

    = logabc

    abc =2

    1

    42. Let x be the solution ..................................Ans. 2

    Sol.A2= A.A = I

    A4= A6= A8=....... = I x = 2,4,6,8,..... .

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    x x(cos sin ) = (cos2+ sin2) + (cos4+ sin4) +

    (cos6+ sin6) + .........= (cos2+ cos4 + cos6 +...) + (sin2 + sin4 + sin6+ .........)

    =

    2

    2

    cos1

    cos+

    2

    2

    sin1

    sin

    = cot2+ tan2minimum value = 2

    43. Let A =

    x61

    x3 2

    ,..................................

    An s. 7Sol. tr(AB) = tr(C)

    3ax2+ b + 6cx = 6x2+ 6x + 4 x R a = 2, b = 4 and c = 1

    44. If A is non-zero square ................................An s. 3

    Sol. I= (I 3A)(I A)

    I =I A 3A + 3A2

    I =I+ ( 2 3)A 2 = 3

    45. If and are roots of the...............................Ans .18Sol. A

    n+1= n+1+ n +1

    = n.+ .n+ n+ n n n = n(+ ) + n(+ ) (n 1 + n 1)

    An+1

    = aAn bA

    n 1

    46. If a, b, c are roots of the ................................Ans .13

    Sol. = abc

    1c1

    c1

    c1

    b

    11

    b

    1

    b

    1a

    1

    a

    11

    a

    1

    R1R1+ R2+ R3

    = abc

    c

    1

    b

    1

    a

    11

    1c

    1

    c

    1

    c

    1b

    11

    b

    1

    b

    1111

    C1C1 C 3 & C2C2 C3

    = (abc + ab + bc + ca)

    1c

    111

    b

    110

    100

    = 11 + 2 = 13

    47. If a, b, c, d respectively ..................................

    Ans .14

    Sol. a, b, c, d are consecutive integer in decreasing order

    a = b2 c2+ d2

    = b2+ (d c) (d + c)

    as d c = 1

    a = b2+ d + c

    b2+ d + c a = 0

    b2+ d + 2 = 0 not possible

    a, b, c, d are in decreasing order

    a = b2 c2+ d2

    = (b c) (b + c) + d 2

    = b + c + d2

    d2+ c = a b

    d2+ c = 1

    d = 0, c = 1, b = 2, a = 3

    a2

    + b2

    + c2

    d2

    = 9 + 4 + 1 + 0 = 14

    48. If [ . ] denotes the greatest...............................Ans . 02Sol. [x]2+ (x)2< 4

    if x , then [x] = (x) = x

    x2< 2 i.e. 2 < x < 2 i .e. x = 1, 0, 1if x , then (x) = 1 + [x] [x]2+ (1 + [x])2< 4i.e. 2[x]2+ 2 [x] 3 < 0

    i.e.4

    282< [x] 2

    1

    n

    n sin i > isin

    icos

    sin2i > cos i1 cos2i > cos icos2i + cos i 1 < 0

    cos i I

    H

    cm

    x yC

    5

    A

    B

    3

    IC= I

    CM+ my2

    = IB

    1 mx2+ my2

    = IB

    1+ m (y2x2) = I

    P + I

    B+ m (y2 x2)

    > IP

    + IB

    > IPHere I

    B1 is moment of inertia of the plate about an axis

    perpendicular to it and passing through B. I

    C> I

    P > I

    B > I

    H

    6. A particle is .........................................Sol . (AC)

    For convex mirror]|m| < 1 for any real objectNow, V

    image= m2 V

    object

    |Vimage

    | < | Vobject

    | always

    7. White light .........................................Sol. (ACD)

    (A) It is true when i = 0.

    (C) By cauchy's formula n = a + 2

    b

    , medium has lowest 'n'for red colour (out of all the colours in white light)V = C/n V is max. for red.(D) = | i r | 1 sin i = n sin rfor violet, n is max r is min. in max.

    8. A convex lens .........................................Sol. (BCD)

    Height of the object h = 2I/I

    h = 6 cm.

    m1=

    h

    I1=

    6

    9=

    2

    3

    m2=

    h

    2=

    6

    4=

    3

    2

    |h|

    |u|=

    2

    3and | u | + | h | = 90

    | u | = 54 cm| h | = 36 cm

    distance between two position

    f =a4

    da 22 =

    904

    )18()90( 22

    = 21.6 cm

    9. Which of the .........................................Ans. (AD)

    10. A prism of r.........................................Sol. (ABC)

    sin C =2

    1c = 45

    for A > 2C no. refractionC < A < 2C some refraction, some reflection

    A < C all refraction.

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    11. At t = 0 the .........................................Sol. (ABD)

    for t = 0x = A sin ........... (1)v = Acos ...........(2)a = A2sin.........(3)

    By (1) and (3)

    =x

    a =

    m08.0

    s/m32 2

    = 20 rad/s

    By (1) and (2)

    vx

    =

    tan tan = 1 or =4 or

    45

    At t = 0 , x is negative hence =4

    5

    from (1) , A = sinx

    = 0.08 2 m = 11.3 cm

    12. (ABC)

    13. (ABCD)

    14. (ABC)

    15. (A) No sliding pure rollingTherefore, acceleration of the tube = 2a (since COM ofcylinders are moving at 'a')

    PA

    = Patm

    + (2a) L (From horizontal limb)

    Also ; PA

    = Patm

    + g

    H (From vertical limb)

    a = L2

    gHAns.

    16. Initially from .........................................

    Sol . (C)

    happ=1

    2h

    when viewed from left side, Lapph =

    2/3

    = 2 cm

    when viewed from right side, Rapph =

    2/3

    17 = 14/3 cm.

    17. The slab in the .........................................

    Sol . (C)

    Here L= 2

    When viewed from left, Lapph =

    2/3

    23= 4 cm

    When viewed from right, Rapph =

    2/3

    27=

    3

    28cm.

    18. Maximum kinetic .........................................So l. (B)

    Maximum KE is acquired by the block when it passes themean position of SHM where F = 0 or mg = kx.

    x = mg/k =200

    10=

    20

    1m

    Applying work energy theorem from position A to B on theblock K

    f K

    i= W

    gravity+ W

    spring

    Kf 2J = 10N

    m

    20

    1+

    2

    20

    1200

    2

    1

    kf= 2.25 J.Ans.

    19. The amplitude .........................................So l. (C)

    KEmax

    =21

    kA2

    A =k

    )KE(2 max=

    200

    )25.2(2=

    400

    9=

    20

    3m =

    15 cm.

    20. Sol . (A) As, dm = Wvdt

    dt

    dm= AAWv

    dt

    dm= VW

    4

    D2

    where D is the diameter of stream.

    21. Sol . (D) V1A1= V2A2

    4

    Dv2

    00=

    4

    Dv 2

    D =v

    vD 00 .

    22. (A)

    Let u be the required minimum velocity. By momentum

    conservation :mu = (m + m)v v = u/2.

    Energy equation :

    2

    1mu2=

    2

    1(2m)v2+ mgH.

    Substituting v = u/2 :

    u = 2 gH

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    23. (A)

    When the block comes to rest, the wedge continues

    to move at V =2

    u= gH on the smooth surface.

    (since, momentum of wedge-block system remains

    conserved).

    24. A small wooden .........................................Sol. (4)

    25. Light travelling .........................................Sol. (1)

    we can use sin x = x (where x is in radians)

    sin2 =2

    3sin r1

    r1=

    3

    4; r2= A r1=

    3

    8

    2

    3sin r2= 3

    4sine e =

    8

    9r2= 3

    = i + e A = 2 + 3 4 = 1

    26. 2

    27. Ans.4

    Sol. (m + m)5

    x= mx + mO

    m + m= 5 m ; m= 4 m

    ;m

    m= 4

    PART-II (Chemistry)

    28. Crystal system in which ..............

    Sol. (C)

    29. How many Zn+2ions are ..........Sol. (A)

    Zn+2 occupy alternate tetrahedral voids

    31. (B)

    32. C

    33. The correct statement(s) ..............Sol. (ABD)

    36. Which of the following crystal ..............

    Sol. (AB)

    cubic and orthorhombic both have simple, body centered, facecentered unit cells.

    37. The distance between nearest ..............Sol. (BC)

    38. Select the correct statement ............Sol. (ABC)

    43. What % of anion sites ..........Sol. (B)

    44. If edge length of unit cell ..........Sol. (D)

    45. Volume of the cube is ..........

    Sol. (D)

    6a2= S,33

    3

    4ar

    46. Ratio of the surface areas ..........

    Sol. (A)

    Ratio =2

    2

    4

    6

    r

    a

    ,

    47.Sol. (B)

    (A) (B)

    (C) (D)

    48.

    Sol. (B)

    Sol.

    4-Ethyl hepta-1,3,5-triene

    51. Atoms from six body centered .............

    Sol. (3)

    Number of unit cell =4

    26

    52. In case of one unit cell of ..............Sol. (8)

    In diamond above shaded plane pass through = 4 corner + 2

    face center + 2 tetrahedral voids so 8 atom.

    PART-III (Mathematics)

    55. The number of integral...................................Sol. (D) (x + a)(x + 1991) = 1

    x + a = 1 and x + 1991 = 1 or x + a = 1 and x + 1991= 1

    a = 1993 or a = 1989

    56. Let and be the roots of the ..............................Sol. (C) + = 1154 and = 1

    2 = + + 2 = 1154 + 2 = 1156 = (34)2

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    = 34

    Again (1/4+ 1/4)2= + 2()1/4= 34 + 2 = 361/4+ 1/4= 6

    57. If A and B are squares ...............................................Sol. (A) AB = A + B

    B = AB A = A(B l) det(B) = det (A) det(B l) = 0 det(B) = 0

    58. B

    59. If adjB = A, |P| = |Q| ...................................Sol. (C)We know that adjA = |A| A1

    adj(Q1BP1) = |Q1BP1|. (Q1BP1)1

    = |P||Q|

    |B|. PB1Q

    = |B|. P. |B|

    1adjB.Q

    = PAQ

    60. If 2576a 456b is ..............................................Sol. (AD) 2576a456b is divisible by 5 b = 0 or 5

    2576a456b is divisible by 3 35 + a + b = 3, Ia = 1, 4, 7, 2, 5, 8.

    61. The value of x ..................................................

    Sol. (AB) Let log2x = A, log

    3x = B, log

    5x = C

    ABC = AB + BC + CA

    1C

    1

    B

    1

    A

    1 , ABC = 0

    A = 0, B = 0, C = 0

    x = 1

    & logx2 + log

    x3 + log

    x5 = 1

    logx30 = 1

    logx30 = 1

    x = 30

    62. If f(x) = |x + 1|...................................Sol. (ABC) f(x) = |x + 1| 2 |x 1|

    (i) x < 1

    f(x) = x 1 + 2x 2 = x 3

    (ii) 1 x 1f(x) = x + 1 + 2x 2 = 3x 1

    ( iii) x > 1f(x) = x + 1 2x + 2 = x + 3

    63. If log|sinx|

    (x2 8x + 23)...................................Sol. (BCD) log

    |sinx|(x2 8x + 23) 3 log

    |sinx|2 > 0

    log|sinx|

    8

    23x8x2

    > 0

    0 < |sin x| < 1 x R {n, (4n 1)2

    } , n I

    x 0,2

    , ,

    2

    3......(i)

    8

    23x8x

    2

    < 1

    x2 8x + 15 < 0 x (3, 5) ......(ii)

    (i) and (ii) x (3, )

    2

    3,

    5,

    2

    3

    64. If a, b are non-zero real...................................Sol.(BCD)

    (A) S = 2+ 2= a2 2bP = 22= b2

    equation is x2 (a2 2b) x + b2= 0

    (B) S =

    1

    +

    1

    = b

    a

    , P =

    1

    .

    1

    = b

    1

    x2+b

    ax +

    b

    1= 0

    bx2+ ax + 1 = 0

    (C) S =

    +

    =

    22=

    b

    b2a2

    P =

    .

    = 1

    x2b

    b2a

    2

    x + 1 = 0 bx2 (a2 2b) x + b = 0

    (D) S = + 2 = a 2P = ( 1) ( 1)= (+ ) + 1= b + a + 1

    equation is x2+ (a + 2)x + (a + b + 1) = 0.65. The equation............................................

    Sol. (BC) 2)x( 45

    xlog)x(log4

    32

    22

    taking log both sides with base 2

    4

    5xlogxlog

    4

    32

    22 log

    2x=

    2

    1

    02xlog5xlog4xlog3 22

    23

    2

    02xlog7xlog31xlog 2222

    log2x = 1,

    3

    1 , 2 x = 2, 2 1/3 ,

    4

    1

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    66. Consider the equation.................................

    Sol. (ABD)25

    125

    log5

    xx2525 =

    2

    1+ log

    52

    2

    )25()25( xx = 5

    Let t25 x ..........(i)

    t +t

    1= 52

    t2 52 t + 1 = 0 t = 25 , 25Putting these values of t in (i) we get x = 1, 1

    67. If f() =

    sin cos sin

    cos sin cos

    cos sin sin

    ........................

    Sol. (AC) f() = (sin+ cos)(1 sin2)nowf() = 0 tan= 1 or sin2= 1

    =4

    3,

    4

    Also

    2sin1

    )(f= sin+ cos ( 2,2 )

    68. If A1=

    3

    100

    130

    211

    .................................

    Sol. (ABC) |A1| = 1 |A| = 1Now adj A = |A|. A1= A1

    A = (A1)1

    69. If A and B are symmetric...............................Sol. (ABC) Given BT= B and AT= A and AB = BA

    ABA1= BAA1

    B = ABA1

    A1B = A1ABA1

    A1B = BA1

    Similarly AB1= B1A

    Now(A) (A1B)T= BT(A1)T= BT(AT)1= BA1= A1B(B) (AB1)T= (B1)TAT= (BT)1AT= B1A = AB1

    (C) (A1B1)T= (B1)T(A1)T= (BT)1(AT)1= B1A1= A1B1

    70. C .................................Ans . (C)

    71. The value of |B| .................................Ans. (A)

    Sol.(70-71) Let A =

    333231

    232221

    131211

    aaa

    aaa

    aaa

    Now AC = B

    C = A1B = |A|

    1.adjA.B

    C = |A|

    111 21 31

    12 22 32

    13 23 33

    C C C

    C C C

    C C C

    323133313332

    222123212322

    121113111312

    aaaaaa

    aaaaaa

    aaaaaa

    =|A|

    1.

    0|A||A|

    |A|0|A|

    |A||A|0

    C =

    011101

    110

    which is symmetric

    |C| = 2 |A1B| = 2 |B| = 2|A|

    72. If < 0, then the.....................................Ans. (D)73. If a, b, c are rational.......... ............ ......... .

    Ans. (D)

    Sol.=443322

    3322

    22

    111

    111

    11111

    =221

    1

    111

    .

    221

    1

    111

    = {(2 2) (2 ) + 2}2

    = ( )2(+ 1 ( +))2

    =

    a

    c4

    a

    b2

    2 2

    a

    b

    a

    c1

    = 4

    22

    a

    )cba)(ac4b(

    (1) < 0 b2 4ac < 0

    imaginary roots

    (2) ax2+ bx + c = 0 21 , 21

    a

    b= 2 and

    a

    c= 1

    = 32

    74. Number of integral solutions...........................Ans . (C)

    75. Solution set of ............................................Ans . (C)

    Sol. 74 f(x) 0 )4x5x)(1x)(3x2)(1e( 2x2

    0

    )4x)(1x)(1x)(3x2)(1e(2x 0

    Critical points are x = 0, 1, 3/2, 4

    x [1, 1] [3/2, 4]

    also g(x) 0 (x 1)2(x + 1)2 0 x = 1 Number of integral solutions = 2 (x = 1)

  • 8/11/2019 PT-1(JP) 28-04-2013

    10/10

    SOLJPPT12804913 - 10

    75. 0)x(g

    )x(f 22

    2x

    )1x()1x(

    )4x5x)(1x)(3x2)(1e(2

    > 0

    )4x)(1x)(1x)(3x2)(1e(2x 0 x 1

    x (, 1) (1, 3/2] [4, ) {0}

    76. Ans. (A)

    77. Ans. (C)

    78. Ans. 0

    79. The number of values of..........................

    Ans .9

    Sol.

    2

    x+

    4

    x+

    6

    x=

    12

    x11= integer number

    Let x = 12k , then

    2

    x+

    4

    x+

    6

    x= 6k + 3k + 2k = 11k.1k.

    Also12

    x11= 11k

    statement is true for all integeral value of k. x must be multiple of 12. x = 0, 12, 24, 36, 48, 60, 72, 84, 96 which are 9 in number

    80. If A is a square .................................An s. 4

    Sol. |(adjA1)1| = 1

    1

    | adjA |= 21 |A|

    1= |A|2= 4

    81. The entire graph ...............................An s. 6

    Sol. Here for D < 0 , entire graph will be above x-axis

    ( a > 0)

    (k 1)2 36 < 0

    (k 7) (k + 5) < 0 5 < k < 7