Page 1
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
13/04/2023
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)
13/04/2023
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 roots of the equation
2
2 2 0. xx - + = Then
14 14
? + ? is equal to
(1) –64 (2) 64 2 -
(3) –128 (4) 128 2 -
Answer (3)
Sol.
2
2 2 0 xx - + =
26
2
i
x
?
=
Let
2
1 3 1 3
,2
22
ii +-
? = ? = = ?
2 =?
14 7 2 14 7
2 , 2 ? = ? ? = ?
? ( )
14 14 7
21 ? + ? = -
= –2
7
2. The plane, passing through the points (0, –1, 2) and
(–1, 2, 1) and parallel to the line passing through
(5, 1, –7) and (1, –1, –1), also passes through the
point
(1) (–2, 5, 0) (2) (1, –2, 1)
(3) (2, 0, 1) (4) (0, 5, –2)
Answer (1)
Sol. Let A(0, –1, 2) & B(–1, 2, 1)
So, normal vector to the plane
( ) ( )
ˆ
ˆˆ
ˆ ˆ ˆ
3 1 1 16 10 (14)
6 42
j
ik
n i j k = - - = - - +
--
=
ˆ ˆ ˆ
16 10 14 i j k ++
? Equation of plane
16(x – 0) + 10(y + 1) + 14 (z – 2) = 0
? 8x + 5y + 7z = 9
? Option (1) is correct
3. The statement (p ? (?q)) ? ((?p) ? q) ? ((?p) ? (?q))
is equivalent to _____
(1) (?p) ? q (2) (?p) ? (?q)
(3) p ? (?q) (4) p ? q
Answer (2)
Sol. ( ) ( ) ( ) (~ ) (~ ) (~ ) (~ ) p q p q p q ? ? ? ? ?
= ( ) ( ) ~ ( ~ ) ~ p q q p q ? ? ? ?
= ( ) ~~ p p q ??
= ( ) ( ) ~ ~ ~ p p p q ? ? ?
= ~~ pq ?
4. Let the centre of a circle C be (?, ?) and its radius r
< 8. Let 3x + 4y = 24 and 3x – 4y = 32 be two
tangents and 4x + 3y = 1 be a normal to C. Then
(? – ? + r) is equal to
(1) 7 (2) 5
(3) 6 (4) 9
Answer (1)
Sol. ? (?, ?) lies on 4x + 3y = 1
? 4? + 3? = 1 …(i)
and
3 4 24 3 4 32
55
? + ? - ? - ? -
=
Take (+ve)
3? + 4? – 24 = 3? – 4? – 32
? 8? = –8 ? 1 ? = -
So 1 ?= By equation (i)
And
3 4 24
58
5
r
--
= = ?
Take (–ve)
3? + 4? – 24 = –3? + 4? + 32
6? = 56 ?
56 1 4 28
and 1
6 3 3
? ??
? = ? = -
??
??
For then r > 8
? r = 5, ? = 1, ? = –1
? ? – ? + r = 7
Page 3
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
13/04/2023
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 roots of the equation
2
2 2 0. xx - + = Then
14 14
? + ? is equal to
(1) –64 (2) 64 2 -
(3) –128 (4) 128 2 -
Answer (3)
Sol.
2
2 2 0 xx - + =
26
2
i
x
?
=
Let
2
1 3 1 3
,2
22
ii +-
? = ? = = ?
2 =?
14 7 2 14 7
2 , 2 ? = ? ? = ?
? ( )
14 14 7
21 ? + ? = -
= –2
7
2. The plane, passing through the points (0, –1, 2) and
(–1, 2, 1) and parallel to the line passing through
(5, 1, –7) and (1, –1, –1), also passes through the
point
(1) (–2, 5, 0) (2) (1, –2, 1)
(3) (2, 0, 1) (4) (0, 5, –2)
Answer (1)
Sol. Let A(0, –1, 2) & B(–1, 2, 1)
So, normal vector to the plane
( ) ( )
ˆ
ˆˆ
ˆ ˆ ˆ
3 1 1 16 10 (14)
6 42
j
ik
n i j k = - - = - - +
--
=
ˆ ˆ ˆ
16 10 14 i j k ++
? Equation of plane
16(x – 0) + 10(y + 1) + 14 (z – 2) = 0
? 8x + 5y + 7z = 9
? Option (1) is correct
3. The statement (p ? (?q)) ? ((?p) ? q) ? ((?p) ? (?q))
is equivalent to _____
(1) (?p) ? q (2) (?p) ? (?q)
(3) p ? (?q) (4) p ? q
Answer (2)
Sol. ( ) ( ) ( ) (~ ) (~ ) (~ ) (~ ) p q p q p q ? ? ? ? ?
= ( ) ( ) ~ ( ~ ) ~ p q q p q ? ? ? ?
= ( ) ~~ p p q ??
= ( ) ( ) ~ ~ ~ p p p q ? ? ?
= ~~ pq ?
4. Let the centre of a circle C be (?, ?) and its radius r
< 8. Let 3x + 4y = 24 and 3x – 4y = 32 be two
tangents and 4x + 3y = 1 be a normal to C. Then
(? – ? + r) is equal to
(1) 7 (2) 5
(3) 6 (4) 9
Answer (1)
Sol. ? (?, ?) lies on 4x + 3y = 1
? 4? + 3? = 1 …(i)
and
3 4 24 3 4 32
55
? + ? - ? - ? -
=
Take (+ve)
3? + 4? – 24 = 3? – 4? – 32
? 8? = –8 ? 1 ? = -
So 1 ?= By equation (i)
And
3 4 24
58
5
r
--
= = ?
Take (–ve)
3? + 4? – 24 = –3? + 4? + 32
6? = 56 ?
56 1 4 28
and 1
6 3 3
? ??
? = ? = -
??
??
For then r > 8
? r = 5, ? = 1, ? = –1
? ? – ? + r = 7
5. The coefficient of x
5
in the expansion of
5
3
2
1
2
3
x
x
??
-
??
??
is
(1)
80
9
(2) 9
(3) 8 (4)
26
3
Answer (1)
Sol.
( )
5–
53
1
2
–1
2
3
r
r
rr
T C x
x
+
??
=
??
??
15 – 3r – 2r = 5
? r = 2
Coefficient ( )
3
5
2
1 80
2
99
C
??
==
??
??
6. All words, with or without meaning, are made using
all the letters of the word MONDAY. These words
are written as in a dictionary with serial numbers.
The serial number of the word MONDAY is
(1) 327 (2) 328
(3) 324 (4) 326
Answer (1)
Sol.
3 5 4 2 1 6
M O N D A Y
2 3 2 1 0 0
5! 4! 3! 2! 1! 0!
? Rank = (2 × 5! + 3 × 4! + 2 × 3! + 1 × 2!) + 1
= 240 + 72 + 12 + 2 + 1 = 327
7. The value of
( )
4
50
4
0
4
49 51
0
tan
tan tan
x
x
e e xdx
e x x dx
?
?
-
-
?
-
+
+
?
?
is
(1) 51 (2) 50
(3) 25 (4) 49
Answer (2)
Sol.
( )
( )
4
50
4
0
4
49 2
0
tan
tan sec
x
x
e e x dx
e x x dx
?
-?
-
?
-
+
?
?
( )
4
50
4
0
4 50 50
4
0 0
tan
tan tan
50 50
x
xx
e e x dx
e x e x
dx
?
?
-
-
?
?
--
+
=
??
??
??
??
+ ??
??
??
??
??
??
?
?
= 50
8. Let for a triangle ABC,
ˆ ˆ ˆ
23 AB i j k = - + +
ˆ ˆ ˆ
CB i j k = ? + ? + ?
ˆ ˆ ˆ
43 CA i j k = + + ?
If 0 ?? and the area of the triangle ABC is 5 6,
then CB CA ? is equal to
(1) 60 (2) 54
(3) 108 (4) 120
Answer (1)
Sol.
CA + AB = CB
+2i + 4j + (? + 3)k = ?i + ?j + ?k
? ? = +2, ? = 4, ? = ? + 3
Area
11
2 1 3 5 6
22
24
i j k
AB BC = ? = - =
+?
( ) ( )
( )
2
22
12 6 2 100 10 6 = ? - + + ? + =
? 5?
2
= 320
Page 4
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
13/04/2023
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 roots of the equation
2
2 2 0. xx - + = Then
14 14
? + ? is equal to
(1) –64 (2) 64 2 -
(3) –128 (4) 128 2 -
Answer (3)
Sol.
2
2 2 0 xx - + =
26
2
i
x
?
=
Let
2
1 3 1 3
,2
22
ii +-
? = ? = = ?
2 =?
14 7 2 14 7
2 , 2 ? = ? ? = ?
? ( )
14 14 7
21 ? + ? = -
= –2
7
2. The plane, passing through the points (0, –1, 2) and
(–1, 2, 1) and parallel to the line passing through
(5, 1, –7) and (1, –1, –1), also passes through the
point
(1) (–2, 5, 0) (2) (1, –2, 1)
(3) (2, 0, 1) (4) (0, 5, –2)
Answer (1)
Sol. Let A(0, –1, 2) & B(–1, 2, 1)
So, normal vector to the plane
( ) ( )
ˆ
ˆˆ
ˆ ˆ ˆ
3 1 1 16 10 (14)
6 42
j
ik
n i j k = - - = - - +
--
=
ˆ ˆ ˆ
16 10 14 i j k ++
? Equation of plane
16(x – 0) + 10(y + 1) + 14 (z – 2) = 0
? 8x + 5y + 7z = 9
? Option (1) is correct
3. The statement (p ? (?q)) ? ((?p) ? q) ? ((?p) ? (?q))
is equivalent to _____
(1) (?p) ? q (2) (?p) ? (?q)
(3) p ? (?q) (4) p ? q
Answer (2)
Sol. ( ) ( ) ( ) (~ ) (~ ) (~ ) (~ ) p q p q p q ? ? ? ? ?
= ( ) ( ) ~ ( ~ ) ~ p q q p q ? ? ? ?
= ( ) ~~ p p q ??
= ( ) ( ) ~ ~ ~ p p p q ? ? ?
= ~~ pq ?
4. Let the centre of a circle C be (?, ?) and its radius r
< 8. Let 3x + 4y = 24 and 3x – 4y = 32 be two
tangents and 4x + 3y = 1 be a normal to C. Then
(? – ? + r) is equal to
(1) 7 (2) 5
(3) 6 (4) 9
Answer (1)
Sol. ? (?, ?) lies on 4x + 3y = 1
? 4? + 3? = 1 …(i)
and
3 4 24 3 4 32
55
? + ? - ? - ? -
=
Take (+ve)
3? + 4? – 24 = 3? – 4? – 32
? 8? = –8 ? 1 ? = -
So 1 ?= By equation (i)
And
3 4 24
58
5
r
--
= = ?
Take (–ve)
3? + 4? – 24 = –3? + 4? + 32
6? = 56 ?
56 1 4 28
and 1
6 3 3
? ??
? = ? = -
??
??
For then r > 8
? r = 5, ? = 1, ? = –1
? ? – ? + r = 7
5. The coefficient of x
5
in the expansion of
5
3
2
1
2
3
x
x
??
-
??
??
is
(1)
80
9
(2) 9
(3) 8 (4)
26
3
Answer (1)
Sol.
( )
5–
53
1
2
–1
2
3
r
r
rr
T C x
x
+
??
=
??
??
15 – 3r – 2r = 5
? r = 2
Coefficient ( )
3
5
2
1 80
2
99
C
??
==
??
??
6. All words, with or without meaning, are made using
all the letters of the word MONDAY. These words
are written as in a dictionary with serial numbers.
The serial number of the word MONDAY is
(1) 327 (2) 328
(3) 324 (4) 326
Answer (1)
Sol.
3 5 4 2 1 6
M O N D A Y
2 3 2 1 0 0
5! 4! 3! 2! 1! 0!
? Rank = (2 × 5! + 3 × 4! + 2 × 3! + 1 × 2!) + 1
= 240 + 72 + 12 + 2 + 1 = 327
7. The value of
( )
4
50
4
0
4
49 51
0
tan
tan tan
x
x
e e xdx
e x x dx
?
?
-
-
?
-
+
+
?
?
is
(1) 51 (2) 50
(3) 25 (4) 49
Answer (2)
Sol.
( )
( )
4
50
4
0
4
49 2
0
tan
tan sec
x
x
e e x dx
e x x dx
?
-?
-
?
-
+
?
?
( )
4
50
4
0
4 50 50
4
0 0
tan
tan tan
50 50
x
xx
e e x dx
e x e x
dx
?
?
-
-
?
?
--
+
=
??
??
??
??
+ ??
??
??
??
??
??
?
?
= 50
8. Let for a triangle ABC,
ˆ ˆ ˆ
23 AB i j k = - + +
ˆ ˆ ˆ
CB i j k = ? + ? + ?
ˆ ˆ ˆ
43 CA i j k = + + ?
If 0 ?? and the area of the triangle ABC is 5 6,
then CB CA ? is equal to
(1) 60 (2) 54
(3) 108 (4) 120
Answer (1)
Sol.
CA + AB = CB
+2i + 4j + (? + 3)k = ?i + ?j + ?k
? ? = +2, ? = 4, ? = ? + 3
Area
11
2 1 3 5 6
22
24
i j k
AB BC = ? = - =
+?
( ) ( )
( )
2
22
12 6 2 100 10 6 = ? - + + ? + =
? 5?
2
= 320
?
2
= 64
? = 8
? = 5
( )( ) 2 4 8 4 3 5 CB CA i j k i j k ? = + + + +
= 8 + 12 + 40
= 60
9. Let
1 2 3
, , ,..... a a a be a G.P. of increasing positive
numbers. Let the sum of its 6
th
and 8
th
terms be 2
and the product of its 3
rd
and 5
th
terms be
1
9
. Then
2 4 4 6
6( )( ) a a a a ++ is equal to
(1) 3 (2) 33
(3) 2 (4) 22
Answer (1)
Sol. a6 + a8 = 2
? ar
5
+ ar
7
= 2 …(i)
2 2 4
35
11
99
a a a r r ? = ? ? ? =
?
3
1
3
ar =
24
2
33
rr
+=
? r
4
+ r
2
= 6
? (r
2
+ 3) (r
2
– 2) = 0
? r
2
= 2
?
11
2
36
ar ar ? = ? =
Now, 6(a2 + a4) (a4 + a6)
= 6(ar + ar
3
) (ar
3
+ ar
5
)
1 1 1 2
6
6 3 3 3
? ?? ?
= + +
? ?? ?
? ?? ?
1
6 1 3
2
= ? ? =
10. The range of
2
1
2
( ) 4sin
1
x
fx
x
-
??
= ??
??
+
??
is
(1) [0, 2 ] ? (2) [0, ] ?
(3) [0, 2 ) ? (4) [0, ) ?
Answer (3)
Sol.
2
22
1
11
11
x
xx
= - ?
++
?
2
2
01
1
x
x
??
+
?
2
1
2
0 sin
2
1
x
x
-
??
?
?? ??
??
+
??
?
2
1
2
0 4sin 2
1
x
x
-
??
? ? ? ??
??
+
??
? Option (3) is correct.
11. The random variable X follows binomial
distribution B (n, p), for which the difference of the
mean and the variance is 1.
If 2P (X = 2) = 3P (X = 1), then n
2
P (X > 1) is equal
to
(1) 15 (2) 11
(3) 12 (4) 16
Answer (2)
Sol. np – npq = 1
? np(1 – q) = 1
? np
2
= 1
2P(X = 2) = 3P(X = 1)
2 2 1
21
23
n n n n
C p q C p q
--
? = ? ?
?
( ) 1
23
2
nn
p n q
?-
? ? = ? ?
? (n – 1)p = 3(1 – p)
? ( )
2
1
1 3 1 pp
p
??
- = - ??
??
??
?
( )( )
( )
11
31
pp
p
p
-+
=-
? 1 + p = 3p
?
1
2
p =
? n = 4
n
2
P(x > 1) = n
2
(1 – P(x = 1) – P(x = 0))
44
4
1
11
16 1 11
22
C
??
? ? ? ?
?? = - ? - =
? ? ? ?
??
? ? ? ?
??
Option (2) is correct.
Page 5
Answers & Solutions
for
JEE (Main)-2023 (Online) Phase-2
(Mathematics, Physics and Chemistry)
13/04/2023
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 roots of the equation
2
2 2 0. xx - + = Then
14 14
? + ? is equal to
(1) –64 (2) 64 2 -
(3) –128 (4) 128 2 -
Answer (3)
Sol.
2
2 2 0 xx - + =
26
2
i
x
?
=
Let
2
1 3 1 3
,2
22
ii +-
? = ? = = ?
2 =?
14 7 2 14 7
2 , 2 ? = ? ? = ?
? ( )
14 14 7
21 ? + ? = -
= –2
7
2. The plane, passing through the points (0, –1, 2) and
(–1, 2, 1) and parallel to the line passing through
(5, 1, –7) and (1, –1, –1), also passes through the
point
(1) (–2, 5, 0) (2) (1, –2, 1)
(3) (2, 0, 1) (4) (0, 5, –2)
Answer (1)
Sol. Let A(0, –1, 2) & B(–1, 2, 1)
So, normal vector to the plane
( ) ( )
ˆ
ˆˆ
ˆ ˆ ˆ
3 1 1 16 10 (14)
6 42
j
ik
n i j k = - - = - - +
--
=
ˆ ˆ ˆ
16 10 14 i j k ++
? Equation of plane
16(x – 0) + 10(y + 1) + 14 (z – 2) = 0
? 8x + 5y + 7z = 9
? Option (1) is correct
3. The statement (p ? (?q)) ? ((?p) ? q) ? ((?p) ? (?q))
is equivalent to _____
(1) (?p) ? q (2) (?p) ? (?q)
(3) p ? (?q) (4) p ? q
Answer (2)
Sol. ( ) ( ) ( ) (~ ) (~ ) (~ ) (~ ) p q p q p q ? ? ? ? ?
= ( ) ( ) ~ ( ~ ) ~ p q q p q ? ? ? ?
= ( ) ~~ p p q ??
= ( ) ( ) ~ ~ ~ p p p q ? ? ?
= ~~ pq ?
4. Let the centre of a circle C be (?, ?) and its radius r
< 8. Let 3x + 4y = 24 and 3x – 4y = 32 be two
tangents and 4x + 3y = 1 be a normal to C. Then
(? – ? + r) is equal to
(1) 7 (2) 5
(3) 6 (4) 9
Answer (1)
Sol. ? (?, ?) lies on 4x + 3y = 1
? 4? + 3? = 1 …(i)
and
3 4 24 3 4 32
55
? + ? - ? - ? -
=
Take (+ve)
3? + 4? – 24 = 3? – 4? – 32
? 8? = –8 ? 1 ? = -
So 1 ?= By equation (i)
And
3 4 24
58
5
r
--
= = ?
Take (–ve)
3? + 4? – 24 = –3? + 4? + 32
6? = 56 ?
56 1 4 28
and 1
6 3 3
? ??
? = ? = -
??
??
For then r > 8
? r = 5, ? = 1, ? = –1
? ? – ? + r = 7
5. The coefficient of x
5
in the expansion of
5
3
2
1
2
3
x
x
??
-
??
??
is
(1)
80
9
(2) 9
(3) 8 (4)
26
3
Answer (1)
Sol.
( )
5–
53
1
2
–1
2
3
r
r
rr
T C x
x
+
??
=
??
??
15 – 3r – 2r = 5
? r = 2
Coefficient ( )
3
5
2
1 80
2
99
C
??
==
??
??
6. All words, with or without meaning, are made using
all the letters of the word MONDAY. These words
are written as in a dictionary with serial numbers.
The serial number of the word MONDAY is
(1) 327 (2) 328
(3) 324 (4) 326
Answer (1)
Sol.
3 5 4 2 1 6
M O N D A Y
2 3 2 1 0 0
5! 4! 3! 2! 1! 0!
? Rank = (2 × 5! + 3 × 4! + 2 × 3! + 1 × 2!) + 1
= 240 + 72 + 12 + 2 + 1 = 327
7. The value of
( )
4
50
4
0
4
49 51
0
tan
tan tan
x
x
e e xdx
e x x dx
?
?
-
-
?
-
+
+
?
?
is
(1) 51 (2) 50
(3) 25 (4) 49
Answer (2)
Sol.
( )
( )
4
50
4
0
4
49 2
0
tan
tan sec
x
x
e e x dx
e x x dx
?
-?
-
?
-
+
?
?
( )
4
50
4
0
4 50 50
4
0 0
tan
tan tan
50 50
x
xx
e e x dx
e x e x
dx
?
?
-
-
?
?
--
+
=
??
??
??
??
+ ??
??
??
??
??
??
?
?
= 50
8. Let for a triangle ABC,
ˆ ˆ ˆ
23 AB i j k = - + +
ˆ ˆ ˆ
CB i j k = ? + ? + ?
ˆ ˆ ˆ
43 CA i j k = + + ?
If 0 ?? and the area of the triangle ABC is 5 6,
then CB CA ? is equal to
(1) 60 (2) 54
(3) 108 (4) 120
Answer (1)
Sol.
CA + AB = CB
+2i + 4j + (? + 3)k = ?i + ?j + ?k
? ? = +2, ? = 4, ? = ? + 3
Area
11
2 1 3 5 6
22
24
i j k
AB BC = ? = - =
+?
( ) ( )
( )
2
22
12 6 2 100 10 6 = ? - + + ? + =
? 5?
2
= 320
?
2
= 64
? = 8
? = 5
( )( ) 2 4 8 4 3 5 CB CA i j k i j k ? = + + + +
= 8 + 12 + 40
= 60
9. Let
1 2 3
, , ,..... a a a be a G.P. of increasing positive
numbers. Let the sum of its 6
th
and 8
th
terms be 2
and the product of its 3
rd
and 5
th
terms be
1
9
. Then
2 4 4 6
6( )( ) a a a a ++ is equal to
(1) 3 (2) 33
(3) 2 (4) 22
Answer (1)
Sol. a6 + a8 = 2
? ar
5
+ ar
7
= 2 …(i)
2 2 4
35
11
99
a a a r r ? = ? ? ? =
?
3
1
3
ar =
24
2
33
rr
+=
? r
4
+ r
2
= 6
? (r
2
+ 3) (r
2
– 2) = 0
? r
2
= 2
?
11
2
36
ar ar ? = ? =
Now, 6(a2 + a4) (a4 + a6)
= 6(ar + ar
3
) (ar
3
+ ar
5
)
1 1 1 2
6
6 3 3 3
? ?? ?
= + +
? ?? ?
? ?? ?
1
6 1 3
2
= ? ? =
10. The range of
2
1
2
( ) 4sin
1
x
fx
x
-
??
= ??
??
+
??
is
(1) [0, 2 ] ? (2) [0, ] ?
(3) [0, 2 ) ? (4) [0, ) ?
Answer (3)
Sol.
2
22
1
11
11
x
xx
= - ?
++
?
2
2
01
1
x
x
??
+
?
2
1
2
0 sin
2
1
x
x
-
??
?
?? ??
??
+
??
?
2
1
2
0 4sin 2
1
x
x
-
??
? ? ? ??
??
+
??
? Option (3) is correct.
11. The random variable X follows binomial
distribution B (n, p), for which the difference of the
mean and the variance is 1.
If 2P (X = 2) = 3P (X = 1), then n
2
P (X > 1) is equal
to
(1) 15 (2) 11
(3) 12 (4) 16
Answer (2)
Sol. np – npq = 1
? np(1 – q) = 1
? np
2
= 1
2P(X = 2) = 3P(X = 1)
2 2 1
21
23
n n n n
C p q C p q
--
? = ? ?
?
( ) 1
23
2
nn
p n q
?-
? ? = ? ?
? (n – 1)p = 3(1 – p)
? ( )
2
1
1 3 1 pp
p
??
- = - ??
??
??
?
( )( )
( )
11
31
pp
p
p
-+
=-
? 1 + p = 3p
?
1
2
p =
? n = 4
n
2
P(x > 1) = n
2
(1 – P(x = 1) – P(x = 0))
44
4
1
11
16 1 11
22
C
??
? ? ? ?
?? = - ? - =
? ? ? ?
??
? ? ? ?
??
Option (2) is correct.
12. The line, that is coplanar to the line
3 1 5
3 1 5
x y z
, is
(1)
1 2 5
1 2 4
x y z
(2)
1 2 5
1 2 5
x y z
(3)
1 2 5
1 2 5
x y z
(4)
1 2 5
1 2 5
x y z
Answer (2)
Sol. Given line :
3 1 5
3 1 5
x y z + - -
==
-
No line in given options is parallel to given line.
? If two lines are coplanar, then distance between
them must be zero.
Among the given option, only option (2) satisfies
above condition.
2 1 0
3 1 5
1 2 5
--
-
-
= –2(–5) + 1 (–15 + 5) = 0.
? Option (2) is correct.
13. The area of the region
22
, : 4 , 1 x y x y x y is
(1)
( )
4
4 2 1
3
- (2)
( )
4
4 2 1
3
+
(3)
( )
3
4 2 1
4
+ (4)
( )
3
4 2 1
4
-
Answer (1)
Sol.
Required area
22
14
2 4– ydy ydy
??
??
= +
??
??
??
2
3/2
4
3/2
2
1
2(4 – )
2
3 –
3
2
y
y
??
?
?
??
? =
?
??
?
?
?
??
??
( )
4
4 2 – 1
3
=
14. Let 2, 3 ab and the angle between the
vectors a and b be
4
. Then
( ) ( )
2
2 2 3 a b a b + ? - is equal to
(1) 441 (2) 482
(3) 841 (4) 882
Answer (4)
Sol. 2 a =
4 b =
4
ab
?
?=
( ) ( )
2
2 2 3 a b a b +?-
( ) ( )
2
34 a b b a = - ? + ?
( )
2
7ba =?
22
2
49 sin
4
ab
?
=
1
49 4 9
2
? ? ?
= 882
15. If the system of equations
2x + y – z = 5
2x – 5y + ?z = ?
x + 2y – 5z = 7
has infinitely many solutions, then
( ) ( )
22
? + ? + ? - ? is equal to
(1) 904 (2) 916
(3) 912 (4) 920
Answer (2)
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