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Kurian J
Subject: Maths
, asked on 20/3/18
Plz fast....
Explain me this differentiation ?? fAST..
Answer
2
Ujjwal Sancheti
Subject: Maths
, asked on 19/3/18
Will solving each and every question of last 10 years and re-practicing the weak point questions be enough to score 90+ in Maths Board Exam?
Answer
2
Nithyashrri Saravanan
Subject: Maths
, asked on 19/3/18
Q. Find the dimension of a rectangle of perimeter 36 cm, which will sweep out a volume as large as possible , when revolved about one of its sides. Also, find the maximum value.
Answer
1
Archit
Subject: Maths
, asked on 19/3/18
Prove this as an increasing function
9
.
P
r
o
v
e
t
h
a
t
y
=
4
sin
θ
(
2
+
cos
θ
)
-
θ
i
s
a
n
i
n
c
r
e
a
sin
g
f
u
n
c
t
i
o
n
o
f
θ
i
n
0
,
π
2
.
Answer
1
Helen Elma
Subject: Maths
, asked on 18/3/18
Show that
f
(
x
) = sin
x
(1 + cos
x
) is maximum when
a
=
π
3
in the interval [0, π].
Answer
1
Arnapurna Paikaray
Subject: Maths
, asked on 18/3/18
Please explain me Q12 (c) of Exercise 6.2 .
Answer
3
Arnapurna Paikaray
Subject: Maths
, asked on 18/3/18
Please explain (c ) again.Why we took pie instead of 0?
Answer
1
Vibhav
Subject: Maths
, asked on 18/3/18
In this answer the point (4,-8/3) does not satisfy the equation 6y = x^2
So how is this one of the solutions???
Answer
2
Vibhav
Subject: Maths
, asked on 18/3/18
The points on the curve 9
y
2
=
x
3
, where the normal to the curve makes
equal
intercepts with the axes are
(A)
4
,
±
8
3
(B)
4
,
-
8
3
(C)
4
,
±
3
8
(D)
±
4
,
3
8
Answer
1
Suroj Dey
Subject: Maths
, asked on 18/3/18
If f'(x) has no roots, does that mean f(x) will always have at least one root?
Answer
1
Varnika Dhiman
Subject: Maths
, asked on 17/3/18
In the solution of the following question , I want to know how the marked (in blue bracket) step came ?
Q. Find the intervals in which
f
x
=
sin
3
x
-
cos
3
x
,
0
<
x
<
π
is strictly increasing or strictly decreasing?
Answer
1
Varnika Dhiman
Subject: Maths
, asked on 17/3/18
How did we get to know it's "strictly" decreasing or "strictly" increasing ?!..
Why not just decreasing/increasing ?!..
Answer
1
Arnapurna Paikaray
Subject: Maths
, asked on 17/3/18
How area is calculated in this question? Please explain .Dont send links .
Answer
1
Arnapurna Paikaray
Subject: Maths
, asked on 17/3/18
Please explain how it is done. Don't send links .
Solutions:
Ellipse, the area of triangle ABC (A) is given by.
A
=
1
2
a
2
b
a
a
2
-
x
1
2
+
-
x
1
-
b
a
a
2
-
x
1
2
+
-
x
1
⇒
A
=
b
a
2
-
x
1
2
+
x
1
b
a
a
2
-
x
1
2
∴
d
A
d
x
1
=
-
2
x
1
b
2
a
2
-
x
1
2
+
b
a
a
2
-
x
1
2
-
2
b
x
1
2
a
2
a
2
-
x
1
2
=
b
a
a
2
-
x
1
2
-
x
1
a
+
a
2
-
x
1
2
-
x
1
2
N
o
w
.
d
A
d
x
1
=
0
⇒
-
2
x
1
2
-
x
1
a
+
a
2
=
+
⇒
x
1
=
a
±
a
2
-
4
-
1
a
2
2
-
2
Answer
1
Arnapurna Paikaray
Subject: Maths
, asked on 17/3/18
Please explain how perpendicular distance came . Dont provide link please.
Solution:
The equation of the normal at a given point (x,y) is given by,
v
-
a
sin
θ
+
a
θ
cos
θ
=
-
1
t
e
n
θ
x
-
a
cos
θ
-
a
θ
sin
θ
⇒
y
sin
θ
-
a
sin
2
θ
+
a
θ
sin
θ
cos
θ
=
x
cos
θ
+
a
cos
2
θ
⇒
x
cos
θ
+
y
sin
g
θ
-
a
sin
2
θ
+
cos
2
θ
=
⇒
x
cos
θ
+
y
sin
θ
-
a
=
0
Now, the perpendicular distance of he normal from the origin is.
-
a
cos
2
θ
+
sin
2
θ
=
-
a
1
=
a
,
which
is
independent
of
Hence, the perpendicular distance of the normal from the origin is constant.
Answer
1
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What are you looking for?
Explain me this differentiation ?? fAST..
Q. Find the dimension of a rectangle of perimeter 36 cm, which will sweep out a volume as large as possible , when revolved about one of its sides. Also, find the maximum value.
So how is this one of the solutions???
(A) (B) (C) (D)
Q. Find the intervals in which is strictly increasing or strictly decreasing?
Why not just decreasing/increasing ?!..
Solutions:
Ellipse, the area of triangle ABC (A) is given by.
Solution:
The equation of the normal at a given point (x,y) is given by,
Now, the perpendicular distance of he normal from the origin is.
Hence, the perpendicular distance of the normal from the origin is constant.