Page 1
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
06/04/2023
Evening
Time : 3 hrs. M.M. : 300
IMPORTANT INSTRUCTIONS:
(1) The test is of 3 hours duration.
(2) The Test Booklet consists of 90 questions. The maximum marks are 300.
(3) There are three parts in the question paper consisting of Mathematics, Physics and Chemistry
having 30 questions in each part of equal weightage. Each part (subject) has two sections.
(i) Section-A: This section contains 20 multiple choice questions which have only one correct
answer. Each question carries 4 marks for correct answer and –1 mark for wrong answer.
(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out
of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks
for correct answer and –1 mark for wrong answer. For Section-B, the answer should be
rounded off to the nearest integer.
Page 2
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
06/04/2023
Evening
Time : 3 hrs. M.M. : 300
IMPORTANT INSTRUCTIONS:
(1) The test is of 3 hours duration.
(2) The Test Booklet consists of 90 questions. The maximum marks are 300.
(3) There are three parts in the question paper consisting of Mathematics, Physics and Chemistry
having 30 questions in each part of equal weightage. Each part (subject) has two sections.
(i) Section-A: This section contains 20 multiple choice questions which have only one correct
answer. Each question carries 4 marks for correct answer and –1 mark for wrong answer.
(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out
of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks
for correct answer and –1 mark for wrong answer. For Section-B, the answer should be
rounded off to the nearest integer.
MATHEMATICS
SECTION - A
Multiple Choice Questions: This section contains 20
multiple choice questions. Each question has 4 choices
(1), (2), (3) and (4), out of which ONLY ONE is correct.
Choose the correct answer:
1.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
is
equal to
(1) 1 (2) 0
(3) 2 (4)
1
2
Answer (2)
Sol.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
Since
1 1
3 2
2 2 1 -?
1 1
5 2
2 2 1 -?
--------------------
11
2 2 1
2 2 1
n+
-?
n ??
?
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
= 0
2. If gcd (m, n) = 1 and 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
= 1012m
2
n then m
2
– n
2
is equal
to
(1) 240 (2) 200
(3) 220 (4) 180
Answer (1)
Sol. 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
=
2
1011 times
3 7 11 (2023) - - - ?+
=
2
1011
[6 (1010)4] (2023)
2
-
++
= 2023(1012)
? 2023 = 17
2
× 7
? m = 17, n = 7
? m
2
– n
2
= 289 – 49
= 240
3. In a group of 100 persons 75 speak English and 40
speak Hindi. Each person speaks at least one of the
two languages. If the number of persons who speak
only English is ? and the number of persons who
speak only Hindi is ?, then the eccentricity of the
ellipse 25(?
2
x
2
+ ?
2
y
2
) = ?
2
?
2
is
(1)
119
12
(2)
117
12
(3)
3 15
12
(4)
129
12
Answer (1)
Sol.
Now ? = 100 – 75 = 25
? ? = 75 – [40 – 25]
= 60
Now, ellipse
22
22
25 1
(60) 25
xy
??
+= ??
??
??
?
22
1
36 4 25
xy
+=
?
?
25 119
1
36 4 12
e = - =
?
4. Let the vectors , , a b c represent three
coterminous edges of a parallelopiped of volume V.
Then the volume of the parallelopiped, whose
coterminous edges are represented by , + a b c
and + 2 + 3 a b c is equal to
(1) 2V (2) 6V
(3) V (4) 3V
Answer (3)
Page 3
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
06/04/2023
Evening
Time : 3 hrs. M.M. : 300
IMPORTANT INSTRUCTIONS:
(1) The test is of 3 hours duration.
(2) The Test Booklet consists of 90 questions. The maximum marks are 300.
(3) There are three parts in the question paper consisting of Mathematics, Physics and Chemistry
having 30 questions in each part of equal weightage. Each part (subject) has two sections.
(i) Section-A: This section contains 20 multiple choice questions which have only one correct
answer. Each question carries 4 marks for correct answer and –1 mark for wrong answer.
(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out
of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks
for correct answer and –1 mark for wrong answer. For Section-B, the answer should be
rounded off to the nearest integer.
MATHEMATICS
SECTION - A
Multiple Choice Questions: This section contains 20
multiple choice questions. Each question has 4 choices
(1), (2), (3) and (4), out of which ONLY ONE is correct.
Choose the correct answer:
1.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
is
equal to
(1) 1 (2) 0
(3) 2 (4)
1
2
Answer (2)
Sol.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
Since
1 1
3 2
2 2 1 -?
1 1
5 2
2 2 1 -?
--------------------
11
2 2 1
2 2 1
n+
-?
n ??
?
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
= 0
2. If gcd (m, n) = 1 and 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
= 1012m
2
n then m
2
– n
2
is equal
to
(1) 240 (2) 200
(3) 220 (4) 180
Answer (1)
Sol. 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
=
2
1011 times
3 7 11 (2023) - - - ?+
=
2
1011
[6 (1010)4] (2023)
2
-
++
= 2023(1012)
? 2023 = 17
2
× 7
? m = 17, n = 7
? m
2
– n
2
= 289 – 49
= 240
3. In a group of 100 persons 75 speak English and 40
speak Hindi. Each person speaks at least one of the
two languages. If the number of persons who speak
only English is ? and the number of persons who
speak only Hindi is ?, then the eccentricity of the
ellipse 25(?
2
x
2
+ ?
2
y
2
) = ?
2
?
2
is
(1)
119
12
(2)
117
12
(3)
3 15
12
(4)
129
12
Answer (1)
Sol.
Now ? = 100 – 75 = 25
? ? = 75 – [40 – 25]
= 60
Now, ellipse
22
22
25 1
(60) 25
xy
??
+= ??
??
??
?
22
1
36 4 25
xy
+=
?
?
25 119
1
36 4 12
e = - =
?
4. Let the vectors , , a b c represent three
coterminous edges of a parallelopiped of volume V.
Then the volume of the parallelopiped, whose
coterminous edges are represented by , + a b c
and + 2 + 3 a b c is equal to
(1) 2V (2) 6V
(3) V (4) 3V
Answer (3)
Sol. [ , , 2 3 ] a b c a b c + + +
=
1 0 0
0 1 1 [ ]
1 2 3
a b c
= [] a b c
= V
5. If the solution curve f(x, y) = 0 of the differential
equation ( ) 1 log log , > 0,
y
ee
dx
x x x e x
dy
+ - =
passes through the points (1, 0) and (?, 2), then a
a
is equal to
(1)
2
2e
e (2)
2
e
e
(3)
2
2e
e (4)
2
2e
e
Answer (1)
Sol. ( ) 1 ln ln
y
dx
x x x e
dy
+ - =
Put x ln x = t
(1 + ln x) dx = dt
?
y
dt
te
dy
-=
I.F
dy
e
-
?
=
= e
–y
y y y
t e e e dy c
--
? = ? +
?
t × e
–y
= y + c
x ln x = y e
y
+ c e
y
Put x = 1, y = 0
? c = 0
Put x = a, y = 2
a ln a = 2e
2
?
2
2 ae
ae =
6. Let f(x) be a function satisfying ( ) ( )
2
, + ? - = ? f x f x
. x ?? Then ( )
0
sin f x x dx
?
?
is equal to
(1)
2
4
?
(2) 2?
2
(3) ?
2
(4)
2
2
?
Answer (3)
Sol.
( )
0
sin I f x x dx
?
=
?
( )
0
sin I f x x dx
?
= ? -
?
( ) ( ) ( )
0
2 sin I x f x f x dx
?
= + ? -
?
2
0
2 sin I x dx
?
=?
?
2
2
0
2 2 sin I x dx
?
=?
?
2
I =?
7. If the tangents at the points P and Q on the circle
22
25 + - + = x y x y meet at the point
9
, 2 ,
4
??
??
??
R
then the area of the triangle PQR is
(1)
5
4
(2)
13
8
(3)
5
8
(4)
13
4
Answer (3)
Sol.
( )
2
2
1
99
2 2 2 5
44
LS
??
= = + - ? + -
??
??
5
4
=
3
3
2 2 2 2
55
24
Area
55
24
RL
RL
??
?
??
??
==
+
? ? ? ?
+
? ? ? ?
? ? ? ?
25
5
8
4 1 8
==
+
Page 4
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
06/04/2023
Evening
Time : 3 hrs. M.M. : 300
IMPORTANT INSTRUCTIONS:
(1) The test is of 3 hours duration.
(2) The Test Booklet consists of 90 questions. The maximum marks are 300.
(3) There are three parts in the question paper consisting of Mathematics, Physics and Chemistry
having 30 questions in each part of equal weightage. Each part (subject) has two sections.
(i) Section-A: This section contains 20 multiple choice questions which have only one correct
answer. Each question carries 4 marks for correct answer and –1 mark for wrong answer.
(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out
of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks
for correct answer and –1 mark for wrong answer. For Section-B, the answer should be
rounded off to the nearest integer.
MATHEMATICS
SECTION - A
Multiple Choice Questions: This section contains 20
multiple choice questions. Each question has 4 choices
(1), (2), (3) and (4), out of which ONLY ONE is correct.
Choose the correct answer:
1.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
is
equal to
(1) 1 (2) 0
(3) 2 (4)
1
2
Answer (2)
Sol.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
Since
1 1
3 2
2 2 1 -?
1 1
5 2
2 2 1 -?
--------------------
11
2 2 1
2 2 1
n+
-?
n ??
?
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
= 0
2. If gcd (m, n) = 1 and 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
= 1012m
2
n then m
2
– n
2
is equal
to
(1) 240 (2) 200
(3) 220 (4) 180
Answer (1)
Sol. 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
=
2
1011 times
3 7 11 (2023) - - - ?+
=
2
1011
[6 (1010)4] (2023)
2
-
++
= 2023(1012)
? 2023 = 17
2
× 7
? m = 17, n = 7
? m
2
– n
2
= 289 – 49
= 240
3. In a group of 100 persons 75 speak English and 40
speak Hindi. Each person speaks at least one of the
two languages. If the number of persons who speak
only English is ? and the number of persons who
speak only Hindi is ?, then the eccentricity of the
ellipse 25(?
2
x
2
+ ?
2
y
2
) = ?
2
?
2
is
(1)
119
12
(2)
117
12
(3)
3 15
12
(4)
129
12
Answer (1)
Sol.
Now ? = 100 – 75 = 25
? ? = 75 – [40 – 25]
= 60
Now, ellipse
22
22
25 1
(60) 25
xy
??
+= ??
??
??
?
22
1
36 4 25
xy
+=
?
?
25 119
1
36 4 12
e = - =
?
4. Let the vectors , , a b c represent three
coterminous edges of a parallelopiped of volume V.
Then the volume of the parallelopiped, whose
coterminous edges are represented by , + a b c
and + 2 + 3 a b c is equal to
(1) 2V (2) 6V
(3) V (4) 3V
Answer (3)
Sol. [ , , 2 3 ] a b c a b c + + +
=
1 0 0
0 1 1 [ ]
1 2 3
a b c
= [] a b c
= V
5. If the solution curve f(x, y) = 0 of the differential
equation ( ) 1 log log , > 0,
y
ee
dx
x x x e x
dy
+ - =
passes through the points (1, 0) and (?, 2), then a
a
is equal to
(1)
2
2e
e (2)
2
e
e
(3)
2
2e
e (4)
2
2e
e
Answer (1)
Sol. ( ) 1 ln ln
y
dx
x x x e
dy
+ - =
Put x ln x = t
(1 + ln x) dx = dt
?
y
dt
te
dy
-=
I.F
dy
e
-
?
=
= e
–y
y y y
t e e e dy c
--
? = ? +
?
t × e
–y
= y + c
x ln x = y e
y
+ c e
y
Put x = 1, y = 0
? c = 0
Put x = a, y = 2
a ln a = 2e
2
?
2
2 ae
ae =
6. Let f(x) be a function satisfying ( ) ( )
2
, + ? - = ? f x f x
. x ?? Then ( )
0
sin f x x dx
?
?
is equal to
(1)
2
4
?
(2) 2?
2
(3) ?
2
(4)
2
2
?
Answer (3)
Sol.
( )
0
sin I f x x dx
?
=
?
( )
0
sin I f x x dx
?
= ? -
?
( ) ( ) ( )
0
2 sin I x f x f x dx
?
= + ? -
?
2
0
2 sin I x dx
?
=?
?
2
2
0
2 2 sin I x dx
?
=?
?
2
I =?
7. If the tangents at the points P and Q on the circle
22
25 + - + = x y x y meet at the point
9
, 2 ,
4
??
??
??
R
then the area of the triangle PQR is
(1)
5
4
(2)
13
8
(3)
5
8
(4)
13
4
Answer (3)
Sol.
( )
2
2
1
99
2 2 2 5
44
LS
??
= = + - ? + -
??
??
5
4
=
3
3
2 2 2 2
55
24
Area
55
24
RL
RL
??
?
??
??
==
+
? ? ? ?
+
? ? ? ?
? ? ? ?
25
5
8
4 1 8
==
+
8. The area bounded by the curves 12 = - + - y x x
and y = 3 is equal to
(1) 4 (2) 6
(3) 3 (4) 5
Answer (1)
Sol.
Area = ? ?
1
1 3 2
2
+?
= 4
9. If the coefficients of x
7
in
11
2
1
2
??
+
??
??
ax
bx
and x
–7
in
11
2
1
3
??
-
??
??
ax
bx
are equal, then
(1) 729ab = 32 (2) 32ab = 729
(3) 64ab = 243 (4) 243ab = 64
Answer (1)
Sol. Coefficient of x
7
in
11
2
1
2
ax
bx
??
+
??
??
( )
11
11 2
1
1
2
r
r
rr
T C ax
bx
-
+
??
=
??
??
( )
11
11 22 3
1
2
r
r
r
r
C a x
b
-
-
??
=
??
??
22 3 7 5 rr - = ? =
Coefficient of x
–7
in
11
2
1
3
ax
bx
??
-
??
??
( )
11
11
1
2
1
3
r
r
rr
T C ax
bx
-
+
??
=-
??
??
11 11 11 3
1
3
r
rr
r
C a x
b
--
??
=-
??
??
11 3 7 6 rr - = - ? =
? ( )
56
6
11 11 5
56
11
23
C a C a
bb
? ? ? ?
=-
? ? ? ?
? ? ? ?
?
6
3 32 ab =
? 729 ab = 32
10. Let the sets A and B denote the domain and range
respectively of the function
( )
1
, fx
xx
=
- ??
??
where
x ??
??
denotes the smallest integer greater than or
equal to x. Then among the statements
( ) ( )
( ) ( )
S1 : 1 , and
S2 : 1 ,
AB
AB
? = ? -
? = ?
(1) Only (S2) is true
(2) Only (S1) is true
(3) Neither (S1) nor (S2) is true
(4) Both (S1) and (S2) are true
Answer (3)
Sol.
( )
? ?
1
fx
xx
=
-
? ?
1
x
=
-
? Domain = ?
11. Let P be a square matrix such that P
2
= I – P. For
? ? ? ? ? , , , , if
??
+ = ? – 29 P P I P and
??
=? – – 13 , P P I P then ? + ? + ? – ? is equal to
(1) 18 (2) 40
(3) 22 (4) 24
Answer (4)
Sol. P
2
= I – P
42
( )( ) – 2 2 3 P I P I P I P P I P = - - = + = -
62
2 5 3 2 5 3( ) 5 8 P I P P I P IP I P = - + = - + = - …(i)
82
5 13 8 13 21 P I P P I P = - + = - …(ii)
(ii) + (i)
86
18 29 P P I P + = -
(ii) – (i)
86
– 8 13 P P I P =-
? = 8, ? = 6, ? = 18, ? = 8
8 + 6 + 18 + 8 = 24
Page 5
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
06/04/2023
Evening
Time : 3 hrs. M.M. : 300
IMPORTANT INSTRUCTIONS:
(1) The test is of 3 hours duration.
(2) The Test Booklet consists of 90 questions. The maximum marks are 300.
(3) There are three parts in the question paper consisting of Mathematics, Physics and Chemistry
having 30 questions in each part of equal weightage. Each part (subject) has two sections.
(i) Section-A: This section contains 20 multiple choice questions which have only one correct
answer. Each question carries 4 marks for correct answer and –1 mark for wrong answer.
(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out
of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks
for correct answer and –1 mark for wrong answer. For Section-B, the answer should be
rounded off to the nearest integer.
MATHEMATICS
SECTION - A
Multiple Choice Questions: This section contains 20
multiple choice questions. Each question has 4 choices
(1), (2), (3) and (4), out of which ONLY ONE is correct.
Choose the correct answer:
1.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
is
equal to
(1) 1 (2) 0
(3) 2 (4)
1
2
Answer (2)
Sol.
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
Since
1 1
3 2
2 2 1 -?
1 1
5 2
2 2 1 -?
--------------------
11
2 2 1
2 2 1
n+
-?
n ??
?
11 1 1 1 1
35 2 2 2 2 1
lim 2 2 2 2 ..... 2 2
n
n
+
??
?? ? ?? ???
??
? ?? ???
- - -
??
? ?? ???
??
?? ? ?? ? ??
= 0
2. If gcd (m, n) = 1 and 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
= 1012m
2
n then m
2
– n
2
is equal
to
(1) 240 (2) 200
(3) 220 (4) 180
Answer (1)
Sol. 1
2
– 2
2
+ 3
2
– 4
2
+ ….. + (2021)
2
– (2022)
2
+ (2023)
2
=
2
1011 times
3 7 11 (2023) - - - ?+
=
2
1011
[6 (1010)4] (2023)
2
-
++
= 2023(1012)
? 2023 = 17
2
× 7
? m = 17, n = 7
? m
2
– n
2
= 289 – 49
= 240
3. In a group of 100 persons 75 speak English and 40
speak Hindi. Each person speaks at least one of the
two languages. If the number of persons who speak
only English is ? and the number of persons who
speak only Hindi is ?, then the eccentricity of the
ellipse 25(?
2
x
2
+ ?
2
y
2
) = ?
2
?
2
is
(1)
119
12
(2)
117
12
(3)
3 15
12
(4)
129
12
Answer (1)
Sol.
Now ? = 100 – 75 = 25
? ? = 75 – [40 – 25]
= 60
Now, ellipse
22
22
25 1
(60) 25
xy
??
+= ??
??
??
?
22
1
36 4 25
xy
+=
?
?
25 119
1
36 4 12
e = - =
?
4. Let the vectors , , a b c represent three
coterminous edges of a parallelopiped of volume V.
Then the volume of the parallelopiped, whose
coterminous edges are represented by , + a b c
and + 2 + 3 a b c is equal to
(1) 2V (2) 6V
(3) V (4) 3V
Answer (3)
Sol. [ , , 2 3 ] a b c a b c + + +
=
1 0 0
0 1 1 [ ]
1 2 3
a b c
= [] a b c
= V
5. If the solution curve f(x, y) = 0 of the differential
equation ( ) 1 log log , > 0,
y
ee
dx
x x x e x
dy
+ - =
passes through the points (1, 0) and (?, 2), then a
a
is equal to
(1)
2
2e
e (2)
2
e
e
(3)
2
2e
e (4)
2
2e
e
Answer (1)
Sol. ( ) 1 ln ln
y
dx
x x x e
dy
+ - =
Put x ln x = t
(1 + ln x) dx = dt
?
y
dt
te
dy
-=
I.F
dy
e
-
?
=
= e
–y
y y y
t e e e dy c
--
? = ? +
?
t × e
–y
= y + c
x ln x = y e
y
+ c e
y
Put x = 1, y = 0
? c = 0
Put x = a, y = 2
a ln a = 2e
2
?
2
2 ae
ae =
6. Let f(x) be a function satisfying ( ) ( )
2
, + ? - = ? f x f x
. x ?? Then ( )
0
sin f x x dx
?
?
is equal to
(1)
2
4
?
(2) 2?
2
(3) ?
2
(4)
2
2
?
Answer (3)
Sol.
( )
0
sin I f x x dx
?
=
?
( )
0
sin I f x x dx
?
= ? -
?
( ) ( ) ( )
0
2 sin I x f x f x dx
?
= + ? -
?
2
0
2 sin I x dx
?
=?
?
2
2
0
2 2 sin I x dx
?
=?
?
2
I =?
7. If the tangents at the points P and Q on the circle
22
25 + - + = x y x y meet at the point
9
, 2 ,
4
??
??
??
R
then the area of the triangle PQR is
(1)
5
4
(2)
13
8
(3)
5
8
(4)
13
4
Answer (3)
Sol.
( )
2
2
1
99
2 2 2 5
44
LS
??
= = + - ? + -
??
??
5
4
=
3
3
2 2 2 2
55
24
Area
55
24
RL
RL
??
?
??
??
==
+
? ? ? ?
+
? ? ? ?
? ? ? ?
25
5
8
4 1 8
==
+
8. The area bounded by the curves 12 = - + - y x x
and y = 3 is equal to
(1) 4 (2) 6
(3) 3 (4) 5
Answer (1)
Sol.
Area = ? ?
1
1 3 2
2
+?
= 4
9. If the coefficients of x
7
in
11
2
1
2
??
+
??
??
ax
bx
and x
–7
in
11
2
1
3
??
-
??
??
ax
bx
are equal, then
(1) 729ab = 32 (2) 32ab = 729
(3) 64ab = 243 (4) 243ab = 64
Answer (1)
Sol. Coefficient of x
7
in
11
2
1
2
ax
bx
??
+
??
??
( )
11
11 2
1
1
2
r
r
rr
T C ax
bx
-
+
??
=
??
??
( )
11
11 22 3
1
2
r
r
r
r
C a x
b
-
-
??
=
??
??
22 3 7 5 rr - = ? =
Coefficient of x
–7
in
11
2
1
3
ax
bx
??
-
??
??
( )
11
11
1
2
1
3
r
r
rr
T C ax
bx
-
+
??
=-
??
??
11 11 11 3
1
3
r
rr
r
C a x
b
--
??
=-
??
??
11 3 7 6 rr - = - ? =
? ( )
56
6
11 11 5
56
11
23
C a C a
bb
? ? ? ?
=-
? ? ? ?
? ? ? ?
?
6
3 32 ab =
? 729 ab = 32
10. Let the sets A and B denote the domain and range
respectively of the function
( )
1
, fx
xx
=
- ??
??
where
x ??
??
denotes the smallest integer greater than or
equal to x. Then among the statements
( ) ( )
( ) ( )
S1 : 1 , and
S2 : 1 ,
AB
AB
? = ? -
? = ?
(1) Only (S2) is true
(2) Only (S1) is true
(3) Neither (S1) nor (S2) is true
(4) Both (S1) and (S2) are true
Answer (3)
Sol.
( )
? ?
1
fx
xx
=
-
? ?
1
x
=
-
? Domain = ?
11. Let P be a square matrix such that P
2
= I – P. For
? ? ? ? ? , , , , if
??
+ = ? – 29 P P I P and
??
=? – – 13 , P P I P then ? + ? + ? – ? is equal to
(1) 18 (2) 40
(3) 22 (4) 24
Answer (4)
Sol. P
2
= I – P
42
( )( ) – 2 2 3 P I P I P I P P I P = - - = + = -
62
2 5 3 2 5 3( ) 5 8 P I P P I P IP I P = - + = - + = - …(i)
82
5 13 8 13 21 P I P P I P = - + = - …(ii)
(ii) + (i)
86
18 29 P P I P + = -
(ii) – (i)
86
– 8 13 P P I P =-
? = 8, ? = 6, ? = 18, ? = 8
8 + 6 + 18 + 8 = 24
12. Among the statements
(S1) : ( ) ( ) ? ? ? (~ ) p q p q is a tautology
(S2) : ( ) ( ) ? ? ? (~ ) q p p q is a contradiction
(1) Neither (S1) and (S2) is True
(2) Both (S1) and (S2) are True
(3) Only (S2) is True
(4) Only (S1) is True
Answer (1)
Sol. S-I : ( ) ( ) ~ p q p q ? ? ?
? ( ) ( ) p q p q ? ? ? ? ?
? ( ) () p p q q ? ? ? ? ?
= ( ) pq ?? (not a tautology)
S-2 : ( ) ( ) q p p q ? ? ? ?
? ( ) ( ) q p p q ? ? ? ? ? ?
? ( ) ( ) q p p q ? ? ? ? ?
= pq ?? (not a contradiction)
13. All the letters of the word PUBLIC are written in all
possible orders and these words are written as in a
dictionary with serial numbers. Then the serial
number of the word PUBLIC is
(1) 576 (2) 578
(3) 580 (4) 582
Answer (4)
Sol.
5 6 1 4 3 2
P U B L I C
4 4 0 2 1 0
5! 4! 3! 2! 1! 0!
Rank = (1 × 1! + 2 × 2! + 4 × 4! + 4 × 5!) + 1
= (1 + 4 + 96 + 480) + 1
= 582
14. Three dice are rolled. If the probability of getting
different numbers on the three dice is ,
p
q
where p
and q are co-prime, then q – p is equal to
(1) 2 (2) 1
(3) 3 (4) 4
Answer (4)
Sol. If numbers are different on all three dice then
number of ways
= 6 × 5 × 4 = 120
3
120 120 5
()
216 9
6
p
PE
q
= = = =
Now, q – p = 9 – 5 = 4
15. Among the statements :
(S1) : 2023
2022
– 1999
2022
is divisible by 8.
(S2) : 13(13)
n
– 11n – 13 is divisible by 144 for
infinitely many n?
(1) Only (S2) is correct
(2) Only (S1) is correct
(3) Both (S1) and (S2) are correct
(4) Both (S1) and (S2) are incorrect
Answer (2)
Sol. (S1) : (2023)
2022
– (1999)
2022
is divisible by 8
We know that (x – y) divides (x
n
– y
n
) n ??
? (2023 – 1999) divides (2023)
2022
– (1999)
2022
? 24 divides
2022 2002
(2023) – (1999)
? 8 will divide
2022 2002
(2023) – (1999)
? (S1) is correct.
(S2) : 13(13) – 11 13
n
n - is divisible by 144 for
n? .
13(1 12) – 11 13
n
n +-
( )
2
0 1 2
13 12 12 ... 12 – 11 13
n n n n n
n
C C C C n + + + + -
2
12 13 11 12 nn ? - + ?
145 144 n+? is not divisible by 144.
? (S2) is incorrect.
16. Let the line L pass through the point (0, 1, 2),
intersect the line
1 2 3
2 3 4
x y z - - -
== and be
parallel to the plane 2x + y – 3z = 4. Then the
distance of the point P(1, –9, 2) from the line L is
(1) 74 (2) 69
(3) 54 (4) 9
Answer (1)
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