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Pranav Shorey
Subject: Maths
, asked on 8/2/18
No links please
Q6. If
b
→
=
c
→
and
c
→
are three vector such that
a
→
.
b
→
=
a
→
.
c
→
then show that
a
→
=
0
→
or
b
→
=
c
→
or
a
→
is perpendicular to
b
→
-
c
→
.
Answer
1
Aditi Sharma
Subject: Maths
, asked on 7/2/18
Plz Solve @20
Q20. Prove that :
a
→
b
→
+
c
→
×
a
→
–
2
b
→
+
3
c
→
=
a
→
b
→
c
→
Answer
1
Austin Mathew
Subject: Maths
, asked on 7/2/18
If vectors a,b and c are three mutually perpendicular vectors of same magnitude, prove that a (vector) +b (vector)+c (vector) is equally inclined with the vectors a, b and c
Answer
1
Guna Shekar
Subject: Maths
, asked on 30/1/18
A particle has initial velocity v=(9i-6j) m/s and a constant force F=(2i+3j)N acts on the particle. The path of the particle will be?
1) Straight line
2) Parabolic
3) Circular
4) Elliptical
Answer
1
Guna Shekar
Subject: Maths
, asked on 30/1/18
Force acting on a particle is (3i+2j). Work done by this force is zero, when the particle is moved on the line 3y+kx=5. Value of k is?
Answer
1
Guna Shekar
Subject: Maths
, asked on 30/1/18
Q
.
19
T
h
e
v
e
c
t
o
r
c
o
m
p
o
n
e
n
t
o
f
v
e
c
t
o
r
A
→
=
i
^
+
3
j
^
a
l
o
n
g
3
i
^
+
j
^
a
n
d
-
i
^
+
3
j
^
1
3
2
j
^
+
3
2
j
^
,
-
i
^
+
3
j
^
2
2
3
i
^
+
j
⏜
,
-
3
2
i
^
+
3
2
j
^
3
i
^
+
1
3
j
^
,
-
i
^
3
+
j
^
4
3
2
i
^
+
3
2
j
^
,
-
i
^
-
3
j
^
Answer
1
Sudipan
Subject: Maths
, asked on 29/1/18
If a,b,c are the lengths of the sides opposite respectively to the angles A,B,C of a triangle ABC, then show by vector method
cos A= (b^2 + c^2 - a^2)/2bc
Answer
1
Snegaa J. S.
Subject: Maths
, asked on 23/1/18
at 8.00 AM ship A is 65 km due east of another ship B . Ship A is then sailing due west at 10km/hr and ship B is sailing due south at 15km/hr . if they continue sailing onh their respective paths , when will they be nearest to one another and how near ? Suggest a way in which fishermen can protect themselves in an emergency.
Answer
1
Kartik Arora
Subject: Maths
, asked on 22/1/18
Q
.
I
f
a
→
=
i
^
+
j
^
,
b
→
=
j
^
+
k
^
,
c
→
=
k
^
+
i
^
f
i
n
d
a
u
n
i
t
v
e
c
t
o
r
i
n
t
h
e
d
i
r
e
c
t
i
o
n
o
f
a
→
+
b
→
+
c
→
.
Answer
1
Tithi
Subject: Maths
, asked on 16/1/18
Solve both. No links please
Answer
1
Shubhrajyoti Ghosh
Subject: Maths
, asked on 15/1/18
No links please
Choose the correct answer from the given alternative :
Qiv). A unit vector perpendicular to both the vectors
i
^
+
j
^
and
j
^
+
k
^
is
-
a)
1
3
i
^
+
j
^
+
k
^
b)
1
3
i
^
-
j
^
+
k
^
c)
1
3
i
^
-
j
^
-
k
^
d)
1
3
-
i
^
-
j
^
+
k
^
Answer
1
Chaitanya Kapoor
Subject: Maths
, asked on 15/1/18
Solve this:
1
)
F
i
n
d
a
^
,
b
^
a
n
d
c
^
a
r
e
m
u
t
u
a
l
l
y
p
e
r
p
e
n
d
i
c
u
l
a
r
u
n
i
t
v
e
c
t
o
r
s
,
t
h
e
n
f
i
n
d
t
h
e
v
a
l
u
e
o
f
2
a
^
+
b
^
+
c
^
.
2
)
S
t
a
t
e
t
h
e
r
e
a
s
o
n
f
o
r
t
h
e
r
e
l
a
t
i
o
n
R
i
n
t
h
e
s
e
t
1
,
2
,
3
g
i
v
e
n
b
R
-
1
,
2
,
2
,
3
n
o
t
t
o
b
e
t
r
a
n
s
i
t
i
v
e
.
I
f
A
i
s
a
m
a
t
r
i
x
o
f
o
r
d
e
r
m
×
n
a
n
d
B
i
s
a
m
a
t
r
i
x
s
u
c
h
t
h
a
t
A
B
'
a
n
d
B
'
A
a
r
e
b
o
t
h
d
e
f
i
n
e
d
,
t
h
e
n
f
i
n
d
t
h
e
o
r
d
e
r
o
f
B
.
3
)
F
i
n
d
*
:
R
→
R
d
e
f
i
n
e
d
b
y
a
*
b
=
a
+
4
b
2
i
s
b
i
n
a
r
y
o
p
e
r
a
t
i
o
n
,
f
i
n
d
5
*
(
2
*
2
)
.
4
)
F
i
n
d
t
h
e
p
r
i
n
c
i
p
a
l
v
a
l
u
e
o
f
tan
-
1
3
-
s
e
c
-
1
(
-
2
)
.
5
)
F
i
n
d
a
n
a
n
g
l
e
θ
,
0
<
θ
<
π
2
,
w
h
i
c
h
i
n
c
r
e
a
s
e
t
w
i
c
e
a
s
f
a
s
t
a
s
i
t
s
sin
e
.
6
)
E
v
a
l
u
a
t
e
∫
x
9
4
x
2
+
1
6
d
x
Answer
1
Aryan
Subject: Maths
, asked on 13/1/18
What would be the length of the longest chord?
Answer
1
Aryan
Subject: Maths
, asked on 13/1/18
What will be the length of the longest chord of a circle that passes through the point (-1,0) and touches the y-axis at (0,2) ?
Answer
1
Dipesh Malhotra
Subject: Maths
, asked on 11/1/18
When are two vectors orthagonal?
Answer
1
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Next
What are you looking for?
Q6. If are three vector such that then show that is perpendicular to .
Q20. Prove that :
1) Straight line
2) Parabolic
3) Circular
4) Elliptical
cos A= (b^2 + c^2 - a^2)/2bc
Choose the correct answer from the given alternative :
Qiv). A unit vector perpendicular to both the vectors
a) b) c) d)