Page 1
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
10/04/2023
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)
10/04/2023
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. Let ? be the mean and ? be the standard deviation
of the distribution
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
where 62.
i
f =
?
If [x] denotes the greatest integer
? x, then [?
2
+ ?
2
] is equal to
(1) 9 (2) 8
(3) 7 (4) 6
Answer (2)
Sol.
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
2 2 2 2
2 2 – 2 3 – 3 4 4 5 – 15 9 7 – 16
62 62
k k k k k k k + + + + + +
? = =
and 62
i
f =
?
? 3k
2
+ 4k – 2 = 62
? 3k
2
+ 4k – 64 = 0
? (3k
+ 16) (k – 4) = 0
4 k ?=
?
156
62
?=
2 2 2 2
2
1 (2 ) 4( – 1) 9( – 1) 16( 1) 25( – 3) 156
–
62 62
k k k k k ? + + + + + ??
?=
??
??
2
2
29 27 – 72
–
62
kk +
=?
500
62
=
?
22
500
62
? + ? = ? [?
2
+ ?
2
] = 8
2. Let the image of the point P(1, 2, 6) in the plane
passing through the points A(1, 2, 0) and B(1, 4, 1)
C(0, 5, 1) be Q(?, ?, ?). Then (?
2
+ ?
2
+ ?
2
) is equal
to
(1) 65 (2) 62
(3) 76 (4) 70
Answer (1)
Sol. Plane passes through the points
A(1, 2, 0), B(1, 4, 1) and C(0, 5, 1)
Normal vector
ˆˆ
ˆ ˆ ˆ
0 2 1 (–1) – (1) 2
–1 3 1
i j k
i j k = = +
= <–1, –1, 2>
? –1(x – 1) –1 (y – 2) + 2z = 0
? x + y – 2z = 3 …(i)
Now image of P(1, 2, 6) in (i)
– 1 – 2 – 6 –2(–9 – 3)
4
1 1 –2 6
x y z
= = = =
? x = 5, y = 6, z = –2
? ? = 5, ? = 6, ? = –2
? ?
2
+ ?
2
+ ?
2
= 65
3. Let the number (22)
2022
+ (2022)
22
leave the
remainder ? when divided by 3 and ? when divided
by 7. Then (?
2
+ ?
2
) is equal to
(1) 20 (2) 13
(3) 5 (4) 10
Answer (3)
Sol. For ? :
2022 22
divisible by 3
(21 1) (2022) ++
= 3K
1
+ 1
For ? : (21 + 1)
2022
+ (2023 – 1)
22
= 7? + 1 + 7? + 1
= 7K2 + 2
So, ? = 1, ? = 2
?
2
+ ?
2
= 5
Page 3
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
10/04/2023
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. Let ? be the mean and ? be the standard deviation
of the distribution
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
where 62.
i
f =
?
If [x] denotes the greatest integer
? x, then [?
2
+ ?
2
] is equal to
(1) 9 (2) 8
(3) 7 (4) 6
Answer (2)
Sol.
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
2 2 2 2
2 2 – 2 3 – 3 4 4 5 – 15 9 7 – 16
62 62
k k k k k k k + + + + + +
? = =
and 62
i
f =
?
? 3k
2
+ 4k – 2 = 62
? 3k
2
+ 4k – 64 = 0
? (3k
+ 16) (k – 4) = 0
4 k ?=
?
156
62
?=
2 2 2 2
2
1 (2 ) 4( – 1) 9( – 1) 16( 1) 25( – 3) 156
–
62 62
k k k k k ? + + + + + ??
?=
??
??
2
2
29 27 – 72
–
62
kk +
=?
500
62
=
?
22
500
62
? + ? = ? [?
2
+ ?
2
] = 8
2. Let the image of the point P(1, 2, 6) in the plane
passing through the points A(1, 2, 0) and B(1, 4, 1)
C(0, 5, 1) be Q(?, ?, ?). Then (?
2
+ ?
2
+ ?
2
) is equal
to
(1) 65 (2) 62
(3) 76 (4) 70
Answer (1)
Sol. Plane passes through the points
A(1, 2, 0), B(1, 4, 1) and C(0, 5, 1)
Normal vector
ˆˆ
ˆ ˆ ˆ
0 2 1 (–1) – (1) 2
–1 3 1
i j k
i j k = = +
= <–1, –1, 2>
? –1(x – 1) –1 (y – 2) + 2z = 0
? x + y – 2z = 3 …(i)
Now image of P(1, 2, 6) in (i)
– 1 – 2 – 6 –2(–9 – 3)
4
1 1 –2 6
x y z
= = = =
? x = 5, y = 6, z = –2
? ? = 5, ? = 6, ? = –2
? ?
2
+ ?
2
+ ?
2
= 65
3. Let the number (22)
2022
+ (2022)
22
leave the
remainder ? when divided by 3 and ? when divided
by 7. Then (?
2
+ ?
2
) is equal to
(1) 20 (2) 13
(3) 5 (4) 10
Answer (3)
Sol. For ? :
2022 22
divisible by 3
(21 1) (2022) ++
= 3K
1
+ 1
For ? : (21 + 1)
2022
+ (2023 – 1)
22
= 7? + 1 + 7? + 1
= 7K2 + 2
So, ? = 1, ? = 2
?
2
+ ?
2
= 5
4. Eight persons are to be transported from city A to
city B in three cars of different makes. If each car
can accommodate at most three persons, then the
number of ways, in which they can be transported,
is
(1) 1120 (2) 3360
(3) 1680 (4) 560
Answer (2)
Sol. Total ways =
8
C
3
×
5
C
3
×
2
C
2
× 3!
= 3360
5. Let
ˆ ˆ ˆ ˆ ˆ ˆ
2 7 , 3 5 a i j k b i k = + - = + and
ˆ ˆ ˆ
– 2 . c i j k =+
Let d be a vector which is perpendicular to both
and ab , and · 12. cd = Then
( ) ( )
ˆ ˆ ˆ
· i j k c d - + - ?
is equal to
(1) 24 (2) 44
(3) 42 (4) 48
Answer (2)
Sol. () d a b = ? ?
ˆ ˆ ˆ
2 7 1
3 0 5
i j k
ab ? = -
=
ˆ ˆ ˆ
(35) 13 21 i j k --
ˆ ˆ ˆ
(35 13 21 ) d i j k = ? - -
(35 13 42) 12 cd ? = ? + - =
? ? = 2
ˆ ˆ ˆ
2 1 1 2
35 13 21
i j k
cd ? = ? -
--
=
ˆ ˆ ˆ
2(47 91 22 ) i j k ++
ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ
( ) ( ) 2( ) (47 91 22 ) 44 i j k c d i j k i j k - + - ? ? = - + - + + =
6. Let f be a continuous function satisfying
( )
( )
2
23
0
4
, 0.
3
t
f x x dx t t + = ? ?
?
Then
2
4
??
?
??
??
??
f is
equal to
(1)
2
2
1
16
??
?
?-
??
??
??
(2)
3
1
16
??
?
-? +
??
??
??
(3)
3
1
16
??
?
?-
??
??
??
(4)
2
2
1
16
??
?
-? +
??
??
??
Answer (3)
Sol.
( ) ( )
2 4 2
24 f t t t t +=
( )
24
2 f t t t +=
( )
24
2 f x x x = - +
Let x
2
= u
( )
2
2 f u u u = - +
( )
2
2 f x x x = - +
24
2
2
42
4
f
??
? ? ?
= - + ?
??
??
??
4
16
-?
= + ?
3
1
16
??
?
= ? -
??
??
??
7. For , , , , ? ? ? ? ? if
22
log
xx
e
xe
x
ex
??
? ? ? ?
?? +
? ? ? ?
??
? ? ? ?
??
?
11
,
??
? ? ? ?
= - +
? ? ? ?
??
? ? ? ?
xx
xe
dx C
ex
where
0
1
!
?
=
=
?
n
e
n
and
C is constant of integration, then ? + 2? + 3? – 4? is
equal to
(1) 1 (2) 4
(3) –4 (4) –8
Answer (2)
Sol.
2
Let
x
x
t
e
??
=
??
??
( ) 2 ln 1 ln x x t -=
( )
11
2 ln 1 2 x x dx dt
xt
??
- + ? =
??
??
1
ln
2
x dx dt
t
=
2
1 1 1 1
1
22
I t dt dt
tt
t
? ? ? ?
= + ? = +
? ? ? ?
? ? ? ?
??
11
2
tC
t
??
= - +
??
??
22
11
22
xx
xe
C
ex
? ? ? ?
= - +
? ? ? ?
? ? ? ?
? ? = 2, ? = 2, ? = 2, ? = 2
? 2 3 4 2 4 6 8 4 ? + ? + ? - ? = + + - =
Page 4
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
10/04/2023
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. Let ? be the mean and ? be the standard deviation
of the distribution
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
where 62.
i
f =
?
If [x] denotes the greatest integer
? x, then [?
2
+ ?
2
] is equal to
(1) 9 (2) 8
(3) 7 (4) 6
Answer (2)
Sol.
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
2 2 2 2
2 2 – 2 3 – 3 4 4 5 – 15 9 7 – 16
62 62
k k k k k k k + + + + + +
? = =
and 62
i
f =
?
? 3k
2
+ 4k – 2 = 62
? 3k
2
+ 4k – 64 = 0
? (3k
+ 16) (k – 4) = 0
4 k ?=
?
156
62
?=
2 2 2 2
2
1 (2 ) 4( – 1) 9( – 1) 16( 1) 25( – 3) 156
–
62 62
k k k k k ? + + + + + ??
?=
??
??
2
2
29 27 – 72
–
62
kk +
=?
500
62
=
?
22
500
62
? + ? = ? [?
2
+ ?
2
] = 8
2. Let the image of the point P(1, 2, 6) in the plane
passing through the points A(1, 2, 0) and B(1, 4, 1)
C(0, 5, 1) be Q(?, ?, ?). Then (?
2
+ ?
2
+ ?
2
) is equal
to
(1) 65 (2) 62
(3) 76 (4) 70
Answer (1)
Sol. Plane passes through the points
A(1, 2, 0), B(1, 4, 1) and C(0, 5, 1)
Normal vector
ˆˆ
ˆ ˆ ˆ
0 2 1 (–1) – (1) 2
–1 3 1
i j k
i j k = = +
= <–1, –1, 2>
? –1(x – 1) –1 (y – 2) + 2z = 0
? x + y – 2z = 3 …(i)
Now image of P(1, 2, 6) in (i)
– 1 – 2 – 6 –2(–9 – 3)
4
1 1 –2 6
x y z
= = = =
? x = 5, y = 6, z = –2
? ? = 5, ? = 6, ? = –2
? ?
2
+ ?
2
+ ?
2
= 65
3. Let the number (22)
2022
+ (2022)
22
leave the
remainder ? when divided by 3 and ? when divided
by 7. Then (?
2
+ ?
2
) is equal to
(1) 20 (2) 13
(3) 5 (4) 10
Answer (3)
Sol. For ? :
2022 22
divisible by 3
(21 1) (2022) ++
= 3K
1
+ 1
For ? : (21 + 1)
2022
+ (2023 – 1)
22
= 7? + 1 + 7? + 1
= 7K2 + 2
So, ? = 1, ? = 2
?
2
+ ?
2
= 5
4. Eight persons are to be transported from city A to
city B in three cars of different makes. If each car
can accommodate at most three persons, then the
number of ways, in which they can be transported,
is
(1) 1120 (2) 3360
(3) 1680 (4) 560
Answer (2)
Sol. Total ways =
8
C
3
×
5
C
3
×
2
C
2
× 3!
= 3360
5. Let
ˆ ˆ ˆ ˆ ˆ ˆ
2 7 , 3 5 a i j k b i k = + - = + and
ˆ ˆ ˆ
– 2 . c i j k =+
Let d be a vector which is perpendicular to both
and ab , and · 12. cd = Then
( ) ( )
ˆ ˆ ˆ
· i j k c d - + - ?
is equal to
(1) 24 (2) 44
(3) 42 (4) 48
Answer (2)
Sol. () d a b = ? ?
ˆ ˆ ˆ
2 7 1
3 0 5
i j k
ab ? = -
=
ˆ ˆ ˆ
(35) 13 21 i j k --
ˆ ˆ ˆ
(35 13 21 ) d i j k = ? - -
(35 13 42) 12 cd ? = ? + - =
? ? = 2
ˆ ˆ ˆ
2 1 1 2
35 13 21
i j k
cd ? = ? -
--
=
ˆ ˆ ˆ
2(47 91 22 ) i j k ++
ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ
( ) ( ) 2( ) (47 91 22 ) 44 i j k c d i j k i j k - + - ? ? = - + - + + =
6. Let f be a continuous function satisfying
( )
( )
2
23
0
4
, 0.
3
t
f x x dx t t + = ? ?
?
Then
2
4
??
?
??
??
??
f is
equal to
(1)
2
2
1
16
??
?
?-
??
??
??
(2)
3
1
16
??
?
-? +
??
??
??
(3)
3
1
16
??
?
?-
??
??
??
(4)
2
2
1
16
??
?
-? +
??
??
??
Answer (3)
Sol.
( ) ( )
2 4 2
24 f t t t t +=
( )
24
2 f t t t +=
( )
24
2 f x x x = - +
Let x
2
= u
( )
2
2 f u u u = - +
( )
2
2 f x x x = - +
24
2
2
42
4
f
??
? ? ?
= - + ?
??
??
??
4
16
-?
= + ?
3
1
16
??
?
= ? -
??
??
??
7. For , , , , ? ? ? ? ? if
22
log
xx
e
xe
x
ex
??
? ? ? ?
?? +
? ? ? ?
??
? ? ? ?
??
?
11
,
??
? ? ? ?
= - +
? ? ? ?
??
? ? ? ?
xx
xe
dx C
ex
where
0
1
!
?
=
=
?
n
e
n
and
C is constant of integration, then ? + 2? + 3? – 4? is
equal to
(1) 1 (2) 4
(3) –4 (4) –8
Answer (2)
Sol.
2
Let
x
x
t
e
??
=
??
??
( ) 2 ln 1 ln x x t -=
( )
11
2 ln 1 2 x x dx dt
xt
??
- + ? =
??
??
1
ln
2
x dx dt
t
=
2
1 1 1 1
1
22
I t dt dt
tt
t
? ? ? ?
= + ? = +
? ? ? ?
? ? ? ?
??
11
2
tC
t
??
= - +
??
??
22
11
22
xx
xe
C
ex
? ? ? ?
= - +
? ? ? ?
? ? ? ?
? ? = 2, ? = 2, ? = 2, ? = 2
? 2 3 4 2 4 6 8 4 ? + ? + ? - ? = + + - =
8. Let ( ) ( ) ( ) ( ) ( ) 1 and 0, 0, 1 . = + - ?? ? ? g x f x f x f x x
If g is decreasing in the interval (0, ?) and
increasing in the interval (?, 1), then tan
–1
(2?) +
11
11
tan tan
--
?+ ? ? ? ?
+
? ? ? ?
??
? ? ? ?
is equal to
(1) ? (2)
5
4
?
(3)
3
4
?
(4)
3
2
?
Answer (1)
Sol. ( ) ( ) ( ) 1 g x f x f x = + -
( ) ( ) ( ) 1 g x f x f x ? = ? - ? -
( ) ( ) ( ) 10 g x f x f x ?? = ?? + ?? - ?
g?(x) is increasing
g?(0) < g?(1)
(0) (1) (1) (0) f f f f ? - ? ? ? - ?
? (0) (1) ff ? ? ?
g?(x) = 0
? ( ) (1 ) f x f x ? = ? -
x = 1 – x
1
2
x =
1
( ) is positive for 0,
2
g x x
??
??
??
??
1
( ) is negative for , 1
2
g x x
??
??
??
??
?
1
2
?=
( )
1 1 1
11
tan 2 tan tan
- - -
?+ ? ? ? ?
? + +
? ? ? ?
??
? ? ? ?
( ) ( ) ( )
1 1 1
tan 1 tan 2 tan 3
- - -
= + +
= ?
9. The statement ( ) ( )
~~?? ??
??
p p q is equivalent to
(1) ( ) ~ ? pq (2) ( ) ( ) ~ ?? p q p
(3) ( ) ( )
~ ?? p q q (4) ( ) ~ ? pq
Answer (4)
Sol. ( ) ( )
~~?? ??
??
p p q
( ) = ~ ~ ~ p p q ??
( ) = ~ ~ p p q ??
( ) ( ) = ~ ~ ~ p p p q ? ? ?
= ~ ~ pq ?
( ) = ~ pq ?
10. Let a circle of radius 4 be concentric to the ellipse
15x
2
+ 19y
2
= 285. Then the common tangents are
inclined to the minor axis of the ellipse at the angle
(1)
3
?
(2)
4
?
(3)
6
?
(4)
12
?
Answer (1)
Sol.
Let the equation of tangent of ellipse be
2
19 15 y mx m = ? +
If it is tangent to circle x
2
+ y
2
= 16
2
2
19 15
4
1
m
m
+
=
+
?
22
19 15 16 16 mm + = +
?
2
31 m =
1
3
m =?
? Angle made by tangent with minor axis i.e., with
y axis is
3
?
Page 5
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
10/04/2023
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. Let ? be the mean and ? be the standard deviation
of the distribution
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
where 62.
i
f =
?
If [x] denotes the greatest integer
? x, then [?
2
+ ?
2
] is equal to
(1) 9 (2) 8
(3) 7 (4) 6
Answer (2)
Sol.
x
i
0 1 2 3 4 5
f
i
k + 2 2k
k
2
– 1 k
2
– 1 k
2
+ 1
k – 3
2 2 2 2
2 2 – 2 3 – 3 4 4 5 – 15 9 7 – 16
62 62
k k k k k k k + + + + + +
? = =
and 62
i
f =
?
? 3k
2
+ 4k – 2 = 62
? 3k
2
+ 4k – 64 = 0
? (3k
+ 16) (k – 4) = 0
4 k ?=
?
156
62
?=
2 2 2 2
2
1 (2 ) 4( – 1) 9( – 1) 16( 1) 25( – 3) 156
–
62 62
k k k k k ? + + + + + ??
?=
??
??
2
2
29 27 – 72
–
62
kk +
=?
500
62
=
?
22
500
62
? + ? = ? [?
2
+ ?
2
] = 8
2. Let the image of the point P(1, 2, 6) in the plane
passing through the points A(1, 2, 0) and B(1, 4, 1)
C(0, 5, 1) be Q(?, ?, ?). Then (?
2
+ ?
2
+ ?
2
) is equal
to
(1) 65 (2) 62
(3) 76 (4) 70
Answer (1)
Sol. Plane passes through the points
A(1, 2, 0), B(1, 4, 1) and C(0, 5, 1)
Normal vector
ˆˆ
ˆ ˆ ˆ
0 2 1 (–1) – (1) 2
–1 3 1
i j k
i j k = = +
= <–1, –1, 2>
? –1(x – 1) –1 (y – 2) + 2z = 0
? x + y – 2z = 3 …(i)
Now image of P(1, 2, 6) in (i)
– 1 – 2 – 6 –2(–9 – 3)
4
1 1 –2 6
x y z
= = = =
? x = 5, y = 6, z = –2
? ? = 5, ? = 6, ? = –2
? ?
2
+ ?
2
+ ?
2
= 65
3. Let the number (22)
2022
+ (2022)
22
leave the
remainder ? when divided by 3 and ? when divided
by 7. Then (?
2
+ ?
2
) is equal to
(1) 20 (2) 13
(3) 5 (4) 10
Answer (3)
Sol. For ? :
2022 22
divisible by 3
(21 1) (2022) ++
= 3K
1
+ 1
For ? : (21 + 1)
2022
+ (2023 – 1)
22
= 7? + 1 + 7? + 1
= 7K2 + 2
So, ? = 1, ? = 2
?
2
+ ?
2
= 5
4. Eight persons are to be transported from city A to
city B in three cars of different makes. If each car
can accommodate at most three persons, then the
number of ways, in which they can be transported,
is
(1) 1120 (2) 3360
(3) 1680 (4) 560
Answer (2)
Sol. Total ways =
8
C
3
×
5
C
3
×
2
C
2
× 3!
= 3360
5. Let
ˆ ˆ ˆ ˆ ˆ ˆ
2 7 , 3 5 a i j k b i k = + - = + and
ˆ ˆ ˆ
– 2 . c i j k =+
Let d be a vector which is perpendicular to both
and ab , and · 12. cd = Then
( ) ( )
ˆ ˆ ˆ
· i j k c d - + - ?
is equal to
(1) 24 (2) 44
(3) 42 (4) 48
Answer (2)
Sol. () d a b = ? ?
ˆ ˆ ˆ
2 7 1
3 0 5
i j k
ab ? = -
=
ˆ ˆ ˆ
(35) 13 21 i j k --
ˆ ˆ ˆ
(35 13 21 ) d i j k = ? - -
(35 13 42) 12 cd ? = ? + - =
? ? = 2
ˆ ˆ ˆ
2 1 1 2
35 13 21
i j k
cd ? = ? -
--
=
ˆ ˆ ˆ
2(47 91 22 ) i j k ++
ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ
( ) ( ) 2( ) (47 91 22 ) 44 i j k c d i j k i j k - + - ? ? = - + - + + =
6. Let f be a continuous function satisfying
( )
( )
2
23
0
4
, 0.
3
t
f x x dx t t + = ? ?
?
Then
2
4
??
?
??
??
??
f is
equal to
(1)
2
2
1
16
??
?
?-
??
??
??
(2)
3
1
16
??
?
-? +
??
??
??
(3)
3
1
16
??
?
?-
??
??
??
(4)
2
2
1
16
??
?
-? +
??
??
??
Answer (3)
Sol.
( ) ( )
2 4 2
24 f t t t t +=
( )
24
2 f t t t +=
( )
24
2 f x x x = - +
Let x
2
= u
( )
2
2 f u u u = - +
( )
2
2 f x x x = - +
24
2
2
42
4
f
??
? ? ?
= - + ?
??
??
??
4
16
-?
= + ?
3
1
16
??
?
= ? -
??
??
??
7. For , , , , ? ? ? ? ? if
22
log
xx
e
xe
x
ex
??
? ? ? ?
?? +
? ? ? ?
??
? ? ? ?
??
?
11
,
??
? ? ? ?
= - +
? ? ? ?
??
? ? ? ?
xx
xe
dx C
ex
where
0
1
!
?
=
=
?
n
e
n
and
C is constant of integration, then ? + 2? + 3? – 4? is
equal to
(1) 1 (2) 4
(3) –4 (4) –8
Answer (2)
Sol.
2
Let
x
x
t
e
??
=
??
??
( ) 2 ln 1 ln x x t -=
( )
11
2 ln 1 2 x x dx dt
xt
??
- + ? =
??
??
1
ln
2
x dx dt
t
=
2
1 1 1 1
1
22
I t dt dt
tt
t
? ? ? ?
= + ? = +
? ? ? ?
? ? ? ?
??
11
2
tC
t
??
= - +
??
??
22
11
22
xx
xe
C
ex
? ? ? ?
= - +
? ? ? ?
? ? ? ?
? ? = 2, ? = 2, ? = 2, ? = 2
? 2 3 4 2 4 6 8 4 ? + ? + ? - ? = + + - =
8. Let ( ) ( ) ( ) ( ) ( ) 1 and 0, 0, 1 . = + - ?? ? ? g x f x f x f x x
If g is decreasing in the interval (0, ?) and
increasing in the interval (?, 1), then tan
–1
(2?) +
11
11
tan tan
--
?+ ? ? ? ?
+
? ? ? ?
??
? ? ? ?
is equal to
(1) ? (2)
5
4
?
(3)
3
4
?
(4)
3
2
?
Answer (1)
Sol. ( ) ( ) ( ) 1 g x f x f x = + -
( ) ( ) ( ) 1 g x f x f x ? = ? - ? -
( ) ( ) ( ) 10 g x f x f x ?? = ?? + ?? - ?
g?(x) is increasing
g?(0) < g?(1)
(0) (1) (1) (0) f f f f ? - ? ? ? - ?
? (0) (1) ff ? ? ?
g?(x) = 0
? ( ) (1 ) f x f x ? = ? -
x = 1 – x
1
2
x =
1
( ) is positive for 0,
2
g x x
??
??
??
??
1
( ) is negative for , 1
2
g x x
??
??
??
??
?
1
2
?=
( )
1 1 1
11
tan 2 tan tan
- - -
?+ ? ? ? ?
? + +
? ? ? ?
??
? ? ? ?
( ) ( ) ( )
1 1 1
tan 1 tan 2 tan 3
- - -
= + +
= ?
9. The statement ( ) ( )
~~?? ??
??
p p q is equivalent to
(1) ( ) ~ ? pq (2) ( ) ( ) ~ ?? p q p
(3) ( ) ( )
~ ?? p q q (4) ( ) ~ ? pq
Answer (4)
Sol. ( ) ( )
~~?? ??
??
p p q
( ) = ~ ~ ~ p p q ??
( ) = ~ ~ p p q ??
( ) ( ) = ~ ~ ~ p p p q ? ? ?
= ~ ~ pq ?
( ) = ~ pq ?
10. Let a circle of radius 4 be concentric to the ellipse
15x
2
+ 19y
2
= 285. Then the common tangents are
inclined to the minor axis of the ellipse at the angle
(1)
3
?
(2)
4
?
(3)
6
?
(4)
12
?
Answer (1)
Sol.
Let the equation of tangent of ellipse be
2
19 15 y mx m = ? +
If it is tangent to circle x
2
+ y
2
= 16
2
2
19 15
4
1
m
m
+
=
+
?
22
19 15 16 16 mm + = +
?
2
31 m =
1
3
m =?
? Angle made by tangent with minor axis i.e., with
y axis is
3
?
11. Let
22
1–tan tan
, : 9 9 10
22
xx
Sx
?? ?? ??
= ? - + =
?? ??
????
and
?
??
?=
??
??
?
2
tan ,
3
xs
x
then ( ) ?-
2 1
14
6
is equal to
(1) 16 (2) 8
(3) 64 (4) 32
Answer (4)
Sol.
22
1 tan tan
9 9 10
xx -
+=
Let
2
tan
9
x
y =
9
10 y
y
+=
?
2
10 9 0 yy - + =
? y = 1, y = 9
22
tan tan
9 1 OR 9 9
xx
==
? tan x = 0 OR tan x = ±1
x = 0 ,
44
x
? -?
=
?
2 2 2 2
tan tan 0 tan tan
3 12 12
xs
x
?
??
? = = + +
?
=
2
2(2 3) -
= 2(7 4 3) -
= 140 – 8 3
?
2
11
( 14) 64 3 32
66
? - = ? ? =
12. Let A = {2, 3, 4} and B = {8, 9, 12}. Then the number
of elements in the relation
= ? ? ?
1 1 2 2 1
{(( , ),( , )) ( , ) : R a b a b A B A B a divides
b
2
and a
2
divides b
1
} is
(1) 36 (2) 24
(3) 18 (4) 12
Answer (1)
Sol. ? ? ? ? 2, 3, 4 , 8, 9, 12 AB ==
12
, a A b B ??
a
1
divides b
2
? ?
12
( , ) (2, 4),(2, 12), (3, 9), (3, 12), (4, 8),(4, 12) ab ?
21
, a A b B ??
a
2
divides b
1
…. same as above…
? Number of relations = 6 × 6 = 36
13. Let a die be rolled n times. Let the probability of
getting odd numbers seven times be equal to the
probability of getting odd numbers nine times. If the
probability of getting even numbers twice is
15
,
2
k
then k is equal to
(1) 60 (2) 15
(3) 90 (4) 30
Answer (1)
Sol. P(getting odd 7 time) = P(getting odd 9 times)
7 7 9 9
79
1 1 1 1
2 2 2 2
nn
nn
CC
--
? ? ? ? ? ? ? ?
=
? ? ? ? ? ? ? ?
? ? ? ? ? ? ? ?
79
nn
CC =
? n = 16
P(2 times even) =
14 2
16
2
11
22
C
? ? ? ?
? ? ? ?
? ? ? ?
=
15 15 15
15 4 60
2 2 2
k ?
==
k = 60
14. Let
? ?
23
: is a real number
42
zi
S z x iy
zi
-
= = +
+
.
Then which of the following is NOT correct?
(1) + + ?
22
1
–
4
y x y
(2)
??
=-
??
??
1
( , ) 0,
2
xy
(3) x = 0
(4)
? ? ? ?
? ? ?
? ? ? ?
? ? ? ?
11
– , – – ,
22
y
Answer (2)
Sol. z x iy =+ and
23
42
zi
zi
-
+
is real number
?
2 (2 3)
4 (4 2)
xyi
x y i
+-
++
is real number.
?
( )( )
22
2 (2 3) 4 (4 2)
(4 ) (4 2)
x y i x y i
xy
+ - - +
++
is real number
? 2 (4 2) (2 3)4 0 x y y x - + + - =
? x = 0
Here x = 0 and y ? but
1
–
2
y ? is not acceptable
in this case
Denominator will be zero.
Hence, option (2) is correct.
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