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 Page 1


   
 
 
   
 
      
 
  
  
PAGE # 1 
 
PART : MATHEMATICS 
 
1. Let A = [aij], B=[bij] are two 3 × 3 matrices such that 
ij
2 j i
ij
a b
? ?
? ? & |B| = 81. Find |A| if ? = 3. 
 ekuk A = [aij], B=[bij], 3 × 3 Øe dh nks vkO;wg bl izdkj gS fd 
ij
2 j i
ij
a b
? ?
? ? rFkk |B| = 81. ;fn ? = 3 gS rc 
|A|dk eku gS&  
(1) 
9
1
   (2) 3   (3) 
81
1
   (4) 
27
1
 
Ans. (1) 
Sol. |B|=
33 32 31
23 22 21
13 12 11
b b b
b b b
b b b
= 
33
4
32
3
31
2
23
3
22
2
21
1
13
2
12
1
11
0
a 3 a 3 a 3
a 3 a 3 a 3
a 3 a 3 a 3
? 81 = 3
3
.3. 3
2 
|A| ??3
4
  = 3
6
 |A| ??|A|= 
9
1
  
 
2. From any point P on the line x = 2y perpendicular is drawn on y = x. Let foot of perpendicular is Q. Find 
the locus of mid point of PQ. 
 js[kk x = 2y ij fLFkr fdlh fcUnq P ls js[kk y = x ij yEc [khapk tkrk gSA ekuk Q yEcikn gS rc PQ ds e/;fcUnq 
dk fcUnqiFk Kkr djks& 
 (1) 2x = 3y   (2) 5x = 7y  (3) 3x = 2y  (4) 7x = 5y 
Ans. (2) 
Sol.  
 
y = x 
Q 
( ?, ?)
P(2 ?, ?) 
x = 2y 
(h,k) 
 
slope of  PQ dh izo.krk = 1
2 h
k
? ?
? ?
? ?
 
 ? ? ?k – ??= – h + 2?? ?
? ? ? ?= 
3
k h ?
 ......(1) 
Also rFkk 2h = 2 ? + ? ?
2k = ? + ? 
? 2h = ? + 2k 
? ? ? = 2h – 2k .....(2) 
from (1)  vkSj & (2)  ls 
) k h ( 2
3
k h
? ?
?
 
so locus is vr% fcUnqiFk 6x –6y = x + y  ? ? ? ?5x = 7y ?
 
Page 2


   
 
 
   
 
      
 
  
  
PAGE # 1 
 
PART : MATHEMATICS 
 
1. Let A = [aij], B=[bij] are two 3 × 3 matrices such that 
ij
2 j i
ij
a b
? ?
? ? & |B| = 81. Find |A| if ? = 3. 
 ekuk A = [aij], B=[bij], 3 × 3 Øe dh nks vkO;wg bl izdkj gS fd 
ij
2 j i
ij
a b
? ?
? ? rFkk |B| = 81. ;fn ? = 3 gS rc 
|A|dk eku gS&  
(1) 
9
1
   (2) 3   (3) 
81
1
   (4) 
27
1
 
Ans. (1) 
Sol. |B|=
33 32 31
23 22 21
13 12 11
b b b
b b b
b b b
= 
33
4
32
3
31
2
23
3
22
2
21
1
13
2
12
1
11
0
a 3 a 3 a 3
a 3 a 3 a 3
a 3 a 3 a 3
? 81 = 3
3
.3. 3
2 
|A| ??3
4
  = 3
6
 |A| ??|A|= 
9
1
  
 
2. From any point P on the line x = 2y perpendicular is drawn on y = x. Let foot of perpendicular is Q. Find 
the locus of mid point of PQ. 
 js[kk x = 2y ij fLFkr fdlh fcUnq P ls js[kk y = x ij yEc [khapk tkrk gSA ekuk Q yEcikn gS rc PQ ds e/;fcUnq 
dk fcUnqiFk Kkr djks& 
 (1) 2x = 3y   (2) 5x = 7y  (3) 3x = 2y  (4) 7x = 5y 
Ans. (2) 
Sol.  
 
y = x 
Q 
( ?, ?)
P(2 ?, ?) 
x = 2y 
(h,k) 
 
slope of  PQ dh izo.krk = 1
2 h
k
? ?
? ?
? ?
 
 ? ? ?k – ??= – h + 2?? ?
? ? ? ?= 
3
k h ?
 ......(1) 
Also rFkk 2h = 2 ? + ? ?
2k = ? + ? 
? 2h = ? + 2k 
? ? ? = 2h – 2k .....(2) 
from (1)  vkSj & (2)  ls 
) k h ( 2
3
k h
? ?
?
 
so locus is vr% fcUnqiFk 6x –6y = x + y  ? ? ? ?5x = 7y ?
 
   
 
 
   
 
      
 
  
  
PAGE # 2 
3. Pair of tangents are drawn from origin to the circle x
2
 + y
2
 – 8x – 4y + 16 = 0 then square of length of 
chord of contact is 
 ewyfcUnq ls o`Ùk x
2
 + y
2
 – 8x – 4y + 16 = 0  ij Li'kZ js[kk,sa [khph tkrh gS rc Li'kZthok dh yEckbZ dk oxZ gS& 
 (1) 
5
64
   (2) 
24
5
   (3) 
8
5
   (4) 
8
13
 
Ans. (1) 
Sol.  L = 4 16 S
1
? ? 
 2 16 4 16 R ? ? ? ? 
 Length of Chord of contact Li'kZthok dh yEckbZ = 
20
16
4 16
2 4 2
R L
LR 2
2 2
?
?
? ?
?
?
 
square of length of chord of contact Li'kZthok dh yEckbZ dk oxZ = 
5
64
 
 
4. Contrapositive of if A ? B and B ? C then C ? D 
 (1) C ? D or  A ? B or  B ? C   (2) C ? D and A ? B or B ? C 
 (3) C ? D or A ? B and B ? C    (4) C ? D or  A ? B or B ? C 
 ;fn A ? B vkSj B ? C rc C ? D dk izfrifjofrZr gS& 
  (1) C ? D ;k A ? B ;k B ? C   (2) C ? D  vkSj A ? B ;k B ? C 
 (3) C ? D;k A ? B  vkSj B ? C    (4) C ? D ;k A ? B ;k B ? C 
Ans. (4) 
Sol. Let P = A ? B, Q = B ? C, R = C ? A  
 Contrapositive of (P ? Q) ? R is ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
Sol. ekuk P = A ? B, Q = B ? C, R = C ? A  
  (P ? Q) ? R  dk izfrifjofrZr ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
 
5. Let y(x) is solution of differential equation (y
2
 – x) 
dx
dy
= 1 and y(0) = 1, then find the value of x where 
curve cuts the x-axis 
 ekuk y(x), vody lehdj.k (y
2
 – x) 
dx
dy
= 1 dk gy gS rFkk y(0) = 1, rc x dk eku gksxk] tgkaa oØ x v{k dks 
izfrPNsn djrk gS& 
  (1) 2 – e  (2) 2 +e   (3) 2   (4) e 
Ans. (1) 
Sol. Sol. 
2
y x
dy
dx
? ? 
 I.F . = 
?
dy . l
e = e
y
 
 x.e
y
 = 
?
dy . e . y
y 2
 
= y
2
.e
y
 – 
?
dy . e . y 2
y
 
Page 3


   
 
 
   
 
      
 
  
  
PAGE # 1 
 
PART : MATHEMATICS 
 
1. Let A = [aij], B=[bij] are two 3 × 3 matrices such that 
ij
2 j i
ij
a b
? ?
? ? & |B| = 81. Find |A| if ? = 3. 
 ekuk A = [aij], B=[bij], 3 × 3 Øe dh nks vkO;wg bl izdkj gS fd 
ij
2 j i
ij
a b
? ?
? ? rFkk |B| = 81. ;fn ? = 3 gS rc 
|A|dk eku gS&  
(1) 
9
1
   (2) 3   (3) 
81
1
   (4) 
27
1
 
Ans. (1) 
Sol. |B|=
33 32 31
23 22 21
13 12 11
b b b
b b b
b b b
= 
33
4
32
3
31
2
23
3
22
2
21
1
13
2
12
1
11
0
a 3 a 3 a 3
a 3 a 3 a 3
a 3 a 3 a 3
? 81 = 3
3
.3. 3
2 
|A| ??3
4
  = 3
6
 |A| ??|A|= 
9
1
  
 
2. From any point P on the line x = 2y perpendicular is drawn on y = x. Let foot of perpendicular is Q. Find 
the locus of mid point of PQ. 
 js[kk x = 2y ij fLFkr fdlh fcUnq P ls js[kk y = x ij yEc [khapk tkrk gSA ekuk Q yEcikn gS rc PQ ds e/;fcUnq 
dk fcUnqiFk Kkr djks& 
 (1) 2x = 3y   (2) 5x = 7y  (3) 3x = 2y  (4) 7x = 5y 
Ans. (2) 
Sol.  
 
y = x 
Q 
( ?, ?)
P(2 ?, ?) 
x = 2y 
(h,k) 
 
slope of  PQ dh izo.krk = 1
2 h
k
? ?
? ?
? ?
 
 ? ? ?k – ??= – h + 2?? ?
? ? ? ?= 
3
k h ?
 ......(1) 
Also rFkk 2h = 2 ? + ? ?
2k = ? + ? 
? 2h = ? + 2k 
? ? ? = 2h – 2k .....(2) 
from (1)  vkSj & (2)  ls 
) k h ( 2
3
k h
? ?
?
 
so locus is vr% fcUnqiFk 6x –6y = x + y  ? ? ? ?5x = 7y ?
 
   
 
 
   
 
      
 
  
  
PAGE # 2 
3. Pair of tangents are drawn from origin to the circle x
2
 + y
2
 – 8x – 4y + 16 = 0 then square of length of 
chord of contact is 
 ewyfcUnq ls o`Ùk x
2
 + y
2
 – 8x – 4y + 16 = 0  ij Li'kZ js[kk,sa [khph tkrh gS rc Li'kZthok dh yEckbZ dk oxZ gS& 
 (1) 
5
64
   (2) 
24
5
   (3) 
8
5
   (4) 
8
13
 
Ans. (1) 
Sol.  L = 4 16 S
1
? ? 
 2 16 4 16 R ? ? ? ? 
 Length of Chord of contact Li'kZthok dh yEckbZ = 
20
16
4 16
2 4 2
R L
LR 2
2 2
?
?
? ?
?
?
 
square of length of chord of contact Li'kZthok dh yEckbZ dk oxZ = 
5
64
 
 
4. Contrapositive of if A ? B and B ? C then C ? D 
 (1) C ? D or  A ? B or  B ? C   (2) C ? D and A ? B or B ? C 
 (3) C ? D or A ? B and B ? C    (4) C ? D or  A ? B or B ? C 
 ;fn A ? B vkSj B ? C rc C ? D dk izfrifjofrZr gS& 
  (1) C ? D ;k A ? B ;k B ? C   (2) C ? D  vkSj A ? B ;k B ? C 
 (3) C ? D;k A ? B  vkSj B ? C    (4) C ? D ;k A ? B ;k B ? C 
Ans. (4) 
Sol. Let P = A ? B, Q = B ? C, R = C ? A  
 Contrapositive of (P ? Q) ? R is ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
Sol. ekuk P = A ? B, Q = B ? C, R = C ? A  
  (P ? Q) ? R  dk izfrifjofrZr ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
 
5. Let y(x) is solution of differential equation (y
2
 – x) 
dx
dy
= 1 and y(0) = 1, then find the value of x where 
curve cuts the x-axis 
 ekuk y(x), vody lehdj.k (y
2
 – x) 
dx
dy
= 1 dk gy gS rFkk y(0) = 1, rc x dk eku gksxk] tgkaa oØ x v{k dks 
izfrPNsn djrk gS& 
  (1) 2 – e  (2) 2 +e   (3) 2   (4) e 
Ans. (1) 
Sol. Sol. 
2
y x
dy
dx
? ? 
 I.F . = 
?
dy . l
e = e
y
 
 x.e
y
 = 
?
dy . e . y
y 2
 
= y
2
.e
y
 – 
?
dy . e . y 2
y
 
   
 
 
   
 
      
 
  
  
PAGE # 3 
? y
2
e
y
 – 2(y.e
y
 –e
y
) + c 
x.e
y
 = y
2
e
y
 –2ye
y
 + 2e
y
 + C 
x = y
2
 –2y + 2 + c. e
–y  
x = 0, y = 1 
0 = 1 – 2 + 2 + 
e
c
 
c = –e  
y = 0, x = 0 – 0 + 2 + (–e) (e
–0
)  
x = 2 –e  
6. Let ?1 and ?2 (where ?1 < ?2)are two solutions of 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) then 
?
?
?
? ?
2
1
d 3 cos
2
 is 
equal to 
 ekuk ?1 vkSj ?2 (tgka ?1 < ?2) lehdj.k 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) ds nks gy gS rc 
?
?
?
? ?
2
1
d 3 cos
2
 dk 
eku gS& 
 (1) 
3
?
   (2) 
3
2 ?
   (3) 
9
?
   (4) 
6
1
3
?
?
 
Ans. (1) 
Sol. 0 4
sin
5
cot 2
2
? ?
?
? ? 
 0 4
sin
5
sin
cos 2
2
2
? ?
?
?
?
?
 
 0 sin 4 sin 5 cos 2
2 2
? ? ? ? ? ? , 0 sin ? ? 
 0 2 sin 5 sin 2
2
? ? ? ? ? 
 0 ) 2 )(sin 1 sin 2 ( ? ? ? ? ? 
 
2
1
sin ? ? 
 
6
5
,
6
? ?
? ? 
 
? ?
?
?
?
?
?
? ?
? ? ? ?
6 / 5
6 /
6 / 5
6 /
2
d
2
6 cos 1
d 3 cos 
 
6 / 5
6 /
6
6 sin
2
1
?
?
?
?
?
?
?
? ?
? ? ? 
?
?
?
?
?
?
? ?
?
?
?
? ) 0 0 (
6
1
6 6
5
2
1
  
3 6
4
.
2
1 ?
?
?
? 
 
7. Let 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 terms = S. If S = (102)m then m = 
 ekuk 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 in rd = S. ;fn S = (102)m rc m = 
  (1) 20    (2) 25   (3) 10   (4) 5 
Ans. (1) 
  
Page 4


   
 
 
   
 
      
 
  
  
PAGE # 1 
 
PART : MATHEMATICS 
 
1. Let A = [aij], B=[bij] are two 3 × 3 matrices such that 
ij
2 j i
ij
a b
? ?
? ? & |B| = 81. Find |A| if ? = 3. 
 ekuk A = [aij], B=[bij], 3 × 3 Øe dh nks vkO;wg bl izdkj gS fd 
ij
2 j i
ij
a b
? ?
? ? rFkk |B| = 81. ;fn ? = 3 gS rc 
|A|dk eku gS&  
(1) 
9
1
   (2) 3   (3) 
81
1
   (4) 
27
1
 
Ans. (1) 
Sol. |B|=
33 32 31
23 22 21
13 12 11
b b b
b b b
b b b
= 
33
4
32
3
31
2
23
3
22
2
21
1
13
2
12
1
11
0
a 3 a 3 a 3
a 3 a 3 a 3
a 3 a 3 a 3
? 81 = 3
3
.3. 3
2 
|A| ??3
4
  = 3
6
 |A| ??|A|= 
9
1
  
 
2. From any point P on the line x = 2y perpendicular is drawn on y = x. Let foot of perpendicular is Q. Find 
the locus of mid point of PQ. 
 js[kk x = 2y ij fLFkr fdlh fcUnq P ls js[kk y = x ij yEc [khapk tkrk gSA ekuk Q yEcikn gS rc PQ ds e/;fcUnq 
dk fcUnqiFk Kkr djks& 
 (1) 2x = 3y   (2) 5x = 7y  (3) 3x = 2y  (4) 7x = 5y 
Ans. (2) 
Sol.  
 
y = x 
Q 
( ?, ?)
P(2 ?, ?) 
x = 2y 
(h,k) 
 
slope of  PQ dh izo.krk = 1
2 h
k
? ?
? ?
? ?
 
 ? ? ?k – ??= – h + 2?? ?
? ? ? ?= 
3
k h ?
 ......(1) 
Also rFkk 2h = 2 ? + ? ?
2k = ? + ? 
? 2h = ? + 2k 
? ? ? = 2h – 2k .....(2) 
from (1)  vkSj & (2)  ls 
) k h ( 2
3
k h
? ?
?
 
so locus is vr% fcUnqiFk 6x –6y = x + y  ? ? ? ?5x = 7y ?
 
   
 
 
   
 
      
 
  
  
PAGE # 2 
3. Pair of tangents are drawn from origin to the circle x
2
 + y
2
 – 8x – 4y + 16 = 0 then square of length of 
chord of contact is 
 ewyfcUnq ls o`Ùk x
2
 + y
2
 – 8x – 4y + 16 = 0  ij Li'kZ js[kk,sa [khph tkrh gS rc Li'kZthok dh yEckbZ dk oxZ gS& 
 (1) 
5
64
   (2) 
24
5
   (3) 
8
5
   (4) 
8
13
 
Ans. (1) 
Sol.  L = 4 16 S
1
? ? 
 2 16 4 16 R ? ? ? ? 
 Length of Chord of contact Li'kZthok dh yEckbZ = 
20
16
4 16
2 4 2
R L
LR 2
2 2
?
?
? ?
?
?
 
square of length of chord of contact Li'kZthok dh yEckbZ dk oxZ = 
5
64
 
 
4. Contrapositive of if A ? B and B ? C then C ? D 
 (1) C ? D or  A ? B or  B ? C   (2) C ? D and A ? B or B ? C 
 (3) C ? D or A ? B and B ? C    (4) C ? D or  A ? B or B ? C 
 ;fn A ? B vkSj B ? C rc C ? D dk izfrifjofrZr gS& 
  (1) C ? D ;k A ? B ;k B ? C   (2) C ? D  vkSj A ? B ;k B ? C 
 (3) C ? D;k A ? B  vkSj B ? C    (4) C ? D ;k A ? B ;k B ? C 
Ans. (4) 
Sol. Let P = A ? B, Q = B ? C, R = C ? A  
 Contrapositive of (P ? Q) ? R is ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
Sol. ekuk P = A ? B, Q = B ? C, R = C ? A  
  (P ? Q) ? R  dk izfrifjofrZr ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
 
5. Let y(x) is solution of differential equation (y
2
 – x) 
dx
dy
= 1 and y(0) = 1, then find the value of x where 
curve cuts the x-axis 
 ekuk y(x), vody lehdj.k (y
2
 – x) 
dx
dy
= 1 dk gy gS rFkk y(0) = 1, rc x dk eku gksxk] tgkaa oØ x v{k dks 
izfrPNsn djrk gS& 
  (1) 2 – e  (2) 2 +e   (3) 2   (4) e 
Ans. (1) 
Sol. Sol. 
2
y x
dy
dx
? ? 
 I.F . = 
?
dy . l
e = e
y
 
 x.e
y
 = 
?
dy . e . y
y 2
 
= y
2
.e
y
 – 
?
dy . e . y 2
y
 
   
 
 
   
 
      
 
  
  
PAGE # 3 
? y
2
e
y
 – 2(y.e
y
 –e
y
) + c 
x.e
y
 = y
2
e
y
 –2ye
y
 + 2e
y
 + C 
x = y
2
 –2y + 2 + c. e
–y  
x = 0, y = 1 
0 = 1 – 2 + 2 + 
e
c
 
c = –e  
y = 0, x = 0 – 0 + 2 + (–e) (e
–0
)  
x = 2 –e  
6. Let ?1 and ?2 (where ?1 < ?2)are two solutions of 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) then 
?
?
?
? ?
2
1
d 3 cos
2
 is 
equal to 
 ekuk ?1 vkSj ?2 (tgka ?1 < ?2) lehdj.k 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) ds nks gy gS rc 
?
?
?
? ?
2
1
d 3 cos
2
 dk 
eku gS& 
 (1) 
3
?
   (2) 
3
2 ?
   (3) 
9
?
   (4) 
6
1
3
?
?
 
Ans. (1) 
Sol. 0 4
sin
5
cot 2
2
? ?
?
? ? 
 0 4
sin
5
sin
cos 2
2
2
? ?
?
?
?
?
 
 0 sin 4 sin 5 cos 2
2 2
? ? ? ? ? ? , 0 sin ? ? 
 0 2 sin 5 sin 2
2
? ? ? ? ? 
 0 ) 2 )(sin 1 sin 2 ( ? ? ? ? ? 
 
2
1
sin ? ? 
 
6
5
,
6
? ?
? ? 
 
? ?
?
?
?
?
?
? ?
? ? ? ?
6 / 5
6 /
6 / 5
6 /
2
d
2
6 cos 1
d 3 cos 
 
6 / 5
6 /
6
6 sin
2
1
?
?
?
?
?
?
?
? ?
? ? ? 
?
?
?
?
?
?
? ?
?
?
?
? ) 0 0 (
6
1
6 6
5
2
1
  
3 6
4
.
2
1 ?
?
?
? 
 
7. Let 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 terms = S. If S = (102)m then m = 
 ekuk 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 in rd = S. ;fn S = (102)m rc m = 
  (1) 20    (2) 25   (3) 10   (4) 5 
Ans. (1) 
  
   
 
 
   
 
      
 
  
  
PAGE # 4 
Sol. S =  
?
 .40 … … … 19 + 18 + 14 + 13 + 9 + 8 + 4 + 3
? ? ? ? ? ? ? ? ? ? ? ? ?
terms in rd 
 S = 7 + 17 + 27 + 37 + 47 +.........20 terms in rd 
 ? ? 10 ) 19 ( 7 2
2
20
S
40
? ? ? = 10[14 + 190]  = 10[2040] = (102) (20) 
 ? m  = 20 
 
8. If ? ? ? ?
r
35 2
1 r
36
C 3 k C ? ? ?
?
  6 , then number of ordered pairs (r, k) are –(where k ?I).  
 ;fn ? ? ? ?
r
35 2
1 r
36
C 3 k C ? ? ?
?
  6 , rks Øfer ;qXeksa (r, k) dh la[;k gS –(tgk¡ k ?I). 
 (1) 6   (2) 2   (3) 3    (4) 4 
Ans. (4) 
Sol. ? ?
r
2
r
C
35
3 k
C
35
1 r
36
? ? ?
?
 
 k
2
 –3 = 
6
1 r ?
   ??k
2
 = 3 + 
6
1 r ?
 
r can be 5, 35 
for r = 5, k = ±2  
r = 35, k = ±3 
Hence number of order pair = 4 
Hindi. ? ?
r
2
r
C
35
3 k
C
35
1 r
36
? ? ?
?
 
 k
2
 –3 = 
6
1 r ?
   ??k
2
 = 3 + 
6
1 r ?
 
r  5, 35 gks ldrk gSA 
r = 5, ds fy, k = ±2  
r = 35, ds fy,k = ±3 
vr% Øfer ;qXeksa dh la[;k = 4 
 
9. Let 4 ? dx e
2
1 –
| x | –
?
?
 = 5 then ? = 
 ekuk fd 4 ? dx e
2
1 –
| x | –
?
?
 = 5 rks ? = 
 (1) ?n2   (2) ?n 2  (3) ?n
4
3
   (4) ?n
3
4
 
Ans. (1) 
Sol. 5 dx e dx e 4
2
0
x
0
1
x
?
?
?
?
?
?
?
? ?
? ?
? ?
?
?
 
 ? 5
e e
4
2
0
x
0
1
x
?
?
?
?
?
?
?
?
?
?
?
? ?
?
?
?
?
?
?
?
?
?
?
?
? ?
?
?
 
Page 5


   
 
 
   
 
      
 
  
  
PAGE # 1 
 
PART : MATHEMATICS 
 
1. Let A = [aij], B=[bij] are two 3 × 3 matrices such that 
ij
2 j i
ij
a b
? ?
? ? & |B| = 81. Find |A| if ? = 3. 
 ekuk A = [aij], B=[bij], 3 × 3 Øe dh nks vkO;wg bl izdkj gS fd 
ij
2 j i
ij
a b
? ?
? ? rFkk |B| = 81. ;fn ? = 3 gS rc 
|A|dk eku gS&  
(1) 
9
1
   (2) 3   (3) 
81
1
   (4) 
27
1
 
Ans. (1) 
Sol. |B|=
33 32 31
23 22 21
13 12 11
b b b
b b b
b b b
= 
33
4
32
3
31
2
23
3
22
2
21
1
13
2
12
1
11
0
a 3 a 3 a 3
a 3 a 3 a 3
a 3 a 3 a 3
? 81 = 3
3
.3. 3
2 
|A| ??3
4
  = 3
6
 |A| ??|A|= 
9
1
  
 
2. From any point P on the line x = 2y perpendicular is drawn on y = x. Let foot of perpendicular is Q. Find 
the locus of mid point of PQ. 
 js[kk x = 2y ij fLFkr fdlh fcUnq P ls js[kk y = x ij yEc [khapk tkrk gSA ekuk Q yEcikn gS rc PQ ds e/;fcUnq 
dk fcUnqiFk Kkr djks& 
 (1) 2x = 3y   (2) 5x = 7y  (3) 3x = 2y  (4) 7x = 5y 
Ans. (2) 
Sol.  
 
y = x 
Q 
( ?, ?)
P(2 ?, ?) 
x = 2y 
(h,k) 
 
slope of  PQ dh izo.krk = 1
2 h
k
? ?
? ?
? ?
 
 ? ? ?k – ??= – h + 2?? ?
? ? ? ?= 
3
k h ?
 ......(1) 
Also rFkk 2h = 2 ? + ? ?
2k = ? + ? 
? 2h = ? + 2k 
? ? ? = 2h – 2k .....(2) 
from (1)  vkSj & (2)  ls 
) k h ( 2
3
k h
? ?
?
 
so locus is vr% fcUnqiFk 6x –6y = x + y  ? ? ? ?5x = 7y ?
 
   
 
 
   
 
      
 
  
  
PAGE # 2 
3. Pair of tangents are drawn from origin to the circle x
2
 + y
2
 – 8x – 4y + 16 = 0 then square of length of 
chord of contact is 
 ewyfcUnq ls o`Ùk x
2
 + y
2
 – 8x – 4y + 16 = 0  ij Li'kZ js[kk,sa [khph tkrh gS rc Li'kZthok dh yEckbZ dk oxZ gS& 
 (1) 
5
64
   (2) 
24
5
   (3) 
8
5
   (4) 
8
13
 
Ans. (1) 
Sol.  L = 4 16 S
1
? ? 
 2 16 4 16 R ? ? ? ? 
 Length of Chord of contact Li'kZthok dh yEckbZ = 
20
16
4 16
2 4 2
R L
LR 2
2 2
?
?
? ?
?
?
 
square of length of chord of contact Li'kZthok dh yEckbZ dk oxZ = 
5
64
 
 
4. Contrapositive of if A ? B and B ? C then C ? D 
 (1) C ? D or  A ? B or  B ? C   (2) C ? D and A ? B or B ? C 
 (3) C ? D or A ? B and B ? C    (4) C ? D or  A ? B or B ? C 
 ;fn A ? B vkSj B ? C rc C ? D dk izfrifjofrZr gS& 
  (1) C ? D ;k A ? B ;k B ? C   (2) C ? D  vkSj A ? B ;k B ? C 
 (3) C ? D;k A ? B  vkSj B ? C    (4) C ? D ;k A ? B ;k B ? C 
Ans. (4) 
Sol. Let P = A ? B, Q = B ? C, R = C ? A  
 Contrapositive of (P ? Q) ? R is ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
Sol. ekuk P = A ? B, Q = B ? C, R = C ? A  
  (P ? Q) ? R  dk izfrifjofrZr ~ R ? ~ (P ? Q)   
 R ? (~ P ? ~ Q) 
 
5. Let y(x) is solution of differential equation (y
2
 – x) 
dx
dy
= 1 and y(0) = 1, then find the value of x where 
curve cuts the x-axis 
 ekuk y(x), vody lehdj.k (y
2
 – x) 
dx
dy
= 1 dk gy gS rFkk y(0) = 1, rc x dk eku gksxk] tgkaa oØ x v{k dks 
izfrPNsn djrk gS& 
  (1) 2 – e  (2) 2 +e   (3) 2   (4) e 
Ans. (1) 
Sol. Sol. 
2
y x
dy
dx
? ? 
 I.F . = 
?
dy . l
e = e
y
 
 x.e
y
 = 
?
dy . e . y
y 2
 
= y
2
.e
y
 – 
?
dy . e . y 2
y
 
   
 
 
   
 
      
 
  
  
PAGE # 3 
? y
2
e
y
 – 2(y.e
y
 –e
y
) + c 
x.e
y
 = y
2
e
y
 –2ye
y
 + 2e
y
 + C 
x = y
2
 –2y + 2 + c. e
–y  
x = 0, y = 1 
0 = 1 – 2 + 2 + 
e
c
 
c = –e  
y = 0, x = 0 – 0 + 2 + (–e) (e
–0
)  
x = 2 –e  
6. Let ?1 and ?2 (where ?1 < ?2)are two solutions of 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) then 
?
?
?
? ?
2
1
d 3 cos
2
 is 
equal to 
 ekuk ?1 vkSj ?2 (tgka ?1 < ?2) lehdj.k 2cot
2
? – 
? sin
5
+ 4 = 0, ?? ? [0, 2 ?) ds nks gy gS rc 
?
?
?
? ?
2
1
d 3 cos
2
 dk 
eku gS& 
 (1) 
3
?
   (2) 
3
2 ?
   (3) 
9
?
   (4) 
6
1
3
?
?
 
Ans. (1) 
Sol. 0 4
sin
5
cot 2
2
? ?
?
? ? 
 0 4
sin
5
sin
cos 2
2
2
? ?
?
?
?
?
 
 0 sin 4 sin 5 cos 2
2 2
? ? ? ? ? ? , 0 sin ? ? 
 0 2 sin 5 sin 2
2
? ? ? ? ? 
 0 ) 2 )(sin 1 sin 2 ( ? ? ? ? ? 
 
2
1
sin ? ? 
 
6
5
,
6
? ?
? ? 
 
? ?
?
?
?
?
?
? ?
? ? ? ?
6 / 5
6 /
6 / 5
6 /
2
d
2
6 cos 1
d 3 cos 
 
6 / 5
6 /
6
6 sin
2
1
?
?
?
?
?
?
?
? ?
? ? ? 
?
?
?
?
?
?
? ?
?
?
?
? ) 0 0 (
6
1
6 6
5
2
1
  
3 6
4
.
2
1 ?
?
?
? 
 
7. Let 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 terms = S. If S = (102)m then m = 
 ekuk 3 + 4 + 8 + 9 + 13 + 14 + 18 +……….40 in rd = S. ;fn S = (102)m rc m = 
  (1) 20    (2) 25   (3) 10   (4) 5 
Ans. (1) 
  
   
 
 
   
 
      
 
  
  
PAGE # 4 
Sol. S =  
?
 .40 … … … 19 + 18 + 14 + 13 + 9 + 8 + 4 + 3
? ? ? ? ? ? ? ? ? ? ? ? ?
terms in rd 
 S = 7 + 17 + 27 + 37 + 47 +.........20 terms in rd 
 ? ? 10 ) 19 ( 7 2
2
20
S
40
? ? ? = 10[14 + 190]  = 10[2040] = (102) (20) 
 ? m  = 20 
 
8. If ? ? ? ?
r
35 2
1 r
36
C 3 k C ? ? ?
?
  6 , then number of ordered pairs (r, k) are –(where k ?I).  
 ;fn ? ? ? ?
r
35 2
1 r
36
C 3 k C ? ? ?
?
  6 , rks Øfer ;qXeksa (r, k) dh la[;k gS –(tgk¡ k ?I). 
 (1) 6   (2) 2   (3) 3    (4) 4 
Ans. (4) 
Sol. ? ?
r
2
r
C
35
3 k
C
35
1 r
36
? ? ?
?
 
 k
2
 –3 = 
6
1 r ?
   ??k
2
 = 3 + 
6
1 r ?
 
r can be 5, 35 
for r = 5, k = ±2  
r = 35, k = ±3 
Hence number of order pair = 4 
Hindi. ? ?
r
2
r
C
35
3 k
C
35
1 r
36
? ? ?
?
 
 k
2
 –3 = 
6
1 r ?
   ??k
2
 = 3 + 
6
1 r ?
 
r  5, 35 gks ldrk gSA 
r = 5, ds fy, k = ±2  
r = 35, ds fy,k = ±3 
vr% Øfer ;qXeksa dh la[;k = 4 
 
9. Let 4 ? dx e
2
1 –
| x | –
?
?
 = 5 then ? = 
 ekuk fd 4 ? dx e
2
1 –
| x | –
?
?
 = 5 rks ? = 
 (1) ?n2   (2) ?n 2  (3) ?n
4
3
   (4) ?n
3
4
 
Ans. (1) 
Sol. 5 dx e dx e 4
2
0
x
0
1
x
?
?
?
?
?
?
?
? ?
? ?
? ?
?
?
 
 ? 5
e e
4
2
0
x
0
1
x
?
?
?
?
?
?
?
?
?
?
?
? ?
?
?
?
?
?
?
?
?
?
?
?
? ?
?
?
 
   
 
 
   
 
      
 
  
  
PAGE # 5 
 ? 5
1 e e 1
4
2
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
? ? ? ?
 ??4(2 – e
–??
– e
–2 ?
) = 5 Put e
– ?
 = t 
 ?  4t
2
 + 4t – 3 = 0   ??(2t + 3) (2t – 1) = 0 
 ??e
– ?
 = 
2
1
    ? ? ? = ln2  
10. Let f(x) is a five degree polynomial which has critical points x = ±1 and 4
x
) x ( f
2 lim
3
0 x
? ?
?
?
?
?
?
?
?
then which one 
is incorrect. 
 (1) f(x) has minima at x = 1 & maxima at x =  –1 
 (2) f(1) –4f(–1) = 4 
 (3) f(x) is maxima at x = 1 and minima at x = –1 
 (4) f(x) is odd 
 ekuk fd f(x) ,d 5 ?kkr dk cgqin gS ftlds Økafrd fcUnq x = ±1 gS rFkk 4
x
) x ( f
2 lim
3
0 x
? ?
?
?
?
?
?
?
?
rks fuEu esa ls dkSulk 
xyr gSA 
 (1) f(x)  dk x = 1 ij fuEufu"B rFkk x =  –1 ij mfPPk"B gSA 
 (2) f(1) –4f(–1) = 4 
 (3) f(x) dk x = 1 mfPp"B rFkk x = –1 ij fuEuf"B gSA 
 (4) f(x) fo"ke ?kkr gSA 
Ans. (1) 
Sol. f(x) = ax
5  
+bx
4
 + cx
3 
 
4
x
cx bx ax
2 lim
3
3 4 5
0 x
?
?
?
?
?
?
?
?
?
? ?
?
?
?? 2 + c = 4 ? c = 2 
f'(x) = 5ax
4  
+ 4bx
3
 + 6x
2
  
= x
2
 ? ? 6 bx 4 ax 5
2
? ? 
f'(1) = 0  ?  5a + 4b + 6 = 0  
f'(–1) = 0  ?  5a – 4b + 6 = 0  
    b = 0 
    a = – 
5
6
 
    f(x) = 
3 5
x 2 x
5
6
?
?
  
f'(x) = –6x
4
 + 6x
2
  
= 6x
2
 (–x
2
 +1)  
= –6x
2
 (x+1) (x–1) 
 
–1 + 1– 
1– 1 
 
Minimal at x = –1  
Maxima at x = 1 
x = –1 ij fuEufu"B 
x = 1 ij mfPp"B 
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