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Megha Prasadan
Subject: Maths
, asked on 16/3/18
Q) Why didn't we change the units or keep it same?
Let y m be the height of the wall at which the ladder touches. Also, let the foot of the ladder be x
m away from the wall.
Then, by Pythagoras theorem, we have:
x
2
+ y
2
= 25 [Length of the ladder = 5 m]
y
=
25
-
x
2
Then, the rate of change of height (y) with respect to time (t) is given by,
d
y
d
x
=
-
x
25
-
x
2
.
d
x
d
t
It is given that dx/dt = 2 cm/s
d
y
d
t
=
-
2
x
25
-
x
2
Now, when x = 4 m, we have:
d
y
d
t
=
-
2
×
4
25
-
16
=
-
8
3
Hence, the height of the ladder on the wall is decreasing at the rate of 8/3 cm/s.
Answer
5
Arnapurna Paikaray
Subject: Maths
, asked on 16/3/18
Please dont provide link.
Answer
3
Arnapurna Paikaray
Subject: Maths
, asked on 16/3/18
Please explain these step by step .
Answer
1
Ranjit Singh
Subject: Maths
, asked on 16/3/18
Q.28. Find the shortest distance between the line x - y + 1 = 0 and the curve
y
2
=
x
.
Answer
1
Vibhav
Subject: Maths
, asked on 16/3/18
In this question, if I have to verify that pi/3 is the point of maxima via first derivative test then why does it give this as the point of minima???
Prove that pi/3 is the point of maxima via first derivative test???
Q.25 If the sum of lengths of the hypotenuse and a side of a right angles triangle is given, then show that the area of triangle is maximum, where the angle between them is
π
3
,
Answer
1
Vibhav
Subject: Maths
, asked on 16/3/18
How is the rate at which the tip of shadow moving equal to x+y????
Please explain via figure
Answer
0
Manasi Mujumdar
Subject: Maths
, asked on 16/3/18
what is the difference between strictly increasing and increasing and strictly decreasing and decreasing. pls explain using an example and not statements
Answer
2
Laieeqa
Subject: Maths
, asked on 16/3/18
Solve this:
Q. Find the equation of tangent to the curve
3
x
2
-
y
2
=
8
which pass through point
4
3
,
0
Answer
1
Kurian J
Subject: Maths
, asked on 15/3/18
T
h
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f
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c
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r
e
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sin
g
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c
r
e
a
sin
g
i
n
(
-
∞
,
O
]
t
o
(
-
∞
,
0
]
.
L
e
t
h
=
g
∘
f
.
I
f
h
(
0
)
=
0
,
t
h
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n
w
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a
t
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n
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f
h
(
x
)
-
h
(
-
1
)
?
(
A
)
a
l
w
a
y
s
p
o
s
i
t
i
v
e
(
B
)
a
l
w
a
y
s
n
e
g
a
t
i
v
e
(
C
)
s
t
r
i
c
t
l
y
i
n
c
r
e
a
sin
g
(
D
)
n
o
n
e
o
f
t
h
e
s
e
Answer
1
Shubhrajyoti Ghosh
Subject: Maths
, asked on 15/3/18
T
h
e
t
i
m
e
T
o
f
a
c
o
m
p
l
e
t
e
o
s
c
i
l
l
a
t
i
o
n
o
f
a
s
i
m
p
l
e
p
e
n
d
u
l
u
m
o
f
l
e
n
g
t
h
I
i
s
g
i
v
e
n
b
y
t
h
e
e
q
u
a
t
i
o
n
T
=
2
π
l
g
,
w
h
e
r
e
g
i
s
c
o
n
s
tan
t
.
W
h
a
t
i
s
t
h
e
p
e
r
c
e
n
t
a
g
e
e
r
r
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r
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n
T
w
h
e
n
/
i
s
i
n
c
r
e
a
s
d
b
y
1
%
.
Answer
1
Devi Das
Subject: Maths
, asked on 14/3/18
Solve this:
I
f
,
x
1
+
y
+
y
1
+
x
=
0
S
h
o
w
t
h
a
t
,
d
y
d
x
=
-
1
1
+
x
2
Answer
1
Sahil Hariani
Subject: Maths
, asked on 28/2/18
Find the approximate volume of hollow spherical shell whose external and inernal radius is 3cm and 3.0005 respectively
Answer
2
Shanaya
Subject: Maths
, asked on 26/2/18
26
Answer
1
Vinuthna Terala
Subject: Maths
, asked on 25/2/18
17q pls solve n send asap
Answer
2
Vinuthna Terala
Subject: Maths
, asked on 25/2/18
16q or one...find point that q,....pls solve n send
Answer
1
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What are you looking for?
Let y m be the height of the wall at which the ladder touches. Also, let the foot of the ladder be x
m away from the wall.
Then, by Pythagoras theorem, we have:
x2 + y2 = 25 [Length of the ladder = 5 m]
Then, the rate of change of height (y) with respect to time (t) is given by,
It is given that dx/dt = 2 cm/s
Now, when x = 4 m, we have:
Hence, the height of the ladder on the wall is decreasing at the rate of 8/3 cm/s.
Prove that pi/3 is the point of maxima via first derivative test???
Q.25 If the sum of lengths of the hypotenuse and a side of a right angles triangle is given, then show that the area of triangle is maximum, where the angle between them is ,
Please explain via figure
Q. Find the equation of tangent to the curve which pass through point