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Nura Mohammad
Subject: Maths
, asked on 25/11/17
How is the underlined step coming??
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz expain how to solve dis...
25
.
T
h
e
s
e
t
s
S
1
,
S
2
,
S
3
.
.
.
.
.
.
.
.
a
r
e
g
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b
y
S
1
=
2
1
,
S
2
=
3
2
,
5
2
,
S
3
=
4
7
,
7
3
'
10
3
,
S
4
=
5
4
,
9
4
,
13
4
,
17
4
,
.
.
.
.
.
.
.
t
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s
e
t
S
25
i
s
1
)
322
2
)
324
3
)
325
4
)
326
Answer
2
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz expain how to solve dis...:
23. If S
1
={2}, S
2
={3,6}, S
3
={4,8,16}, S
4
={5,10,20,40},..... then the sum of numbers in the set S
15
is .
1) 5(2
15
) 2) 16(2
15
-1)
3) 16 (2
16
-1) 4) 15(5
15
-1)
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
P
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a
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x
p
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22
.
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=
1
+
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2
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1
3
+
.
.
.
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.
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.
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1
n
,
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+
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3
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2
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)
2
n
-
H
n
3
)
n
-
n
+
H
n
4
)
H
n
+
2
n
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz explain how to solve dis...
Q.19.
1
2
tan
x
2
+
1
4
tan
x
4
+
.
.
.
+
1
2
n
tan
x
2
n
=
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz expain how to solve dis...
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
P
l
e
a
s
e
e
x
p
l
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i
n
h
o
w
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s
16
.
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t
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t
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g
e
r
s
n
>
1
,
{
x
(
x
n
-
1
-
n
.
a
n
-
1
)
+
a
n
(
n
-
1
)
}
i
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d
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v
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s
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b
l
e
b
y
1
)
(
x
-
a
)
2
2
)
x
-
a
3
)
2
(
x
-
a
)
4
)
x
+
a
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Q
.
1
+
x
a
1
+
x
x
+
a
1
a
1
a
2
+
.
.
.
.
.
.
.
+
x
x
+
a
1
x
+
a
2
.
.
.
.
.
x
+
a
n
-
1
a
1
a
2
.
.
.
.
.
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.
a
n
=
1
.
x
+
a
1
x
+
a
2
.
.
.
.
x
+
a
n
a
1
a
2
.
.
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2
.
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a
1
x
-
a
2
.
.
.
.
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-
a
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1
a
2
.
.
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.
a
n
3
.
x
+
a
1
x
+
a
2
.
.
.
.
x
+
a
n
4
.
x
-
a
1
x
-
a
2
.
.
.
.
x
-
a
n
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz explain how to solve dis...
Q.3.
∑
k
=
1
n
k
1
+
1
n
k
-
1
=
Answer
2
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz explain how to solve dis...
1) n (n - 1)
2) n (n + 1)
3)
n
2
4)
n
+
1
2
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz expain how to solve dis...
V
n
∈
N
1
)
sin
(
n
x
)
<
sin
x
2
)
sin
(
n
x
)
<
n
sin
x
3
)
sin
(
n
x
)
≤
n
sin
x
4
)
sin
(
n
x
)
≤
sin
n
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 27/10/17
Plz expain how to solve dis...
∀
n
∈
N
,
1
+
2
x
+
3
x
2
+
.
.
.
.
.
.
.
+
n
.
x
n
-
1
=
(
x
∈
R
,
X
≠
1
)
1
)
1
-
(
n
+
1
)
x
n
+
n
.
x
n
+
1
1
-
x
2
2
)
n
+
1
x
n
1
-
x
2
3
)
1
-
(
n
+
1
)
x
n
+
n
.
x
n
+
1
1
+
x
2
4
)
n
-
1
x
n
1
+
x
2
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 26/10/17
∀
n
∈
N
,
1
+
2
x
+
3
x
2
+
.
.
.
.
+
n
.
x
n
-
1
=
(
x
∈
R
,
x
≠
1
)
1
)
1
-
(
n
+
1
)
x
n
+
n
.
x
n
+
1
(
1
-
x
)
2
2
)
(
n
+
1
)
x
n
(
1
-
x
)
2
3
)
1
-
(
n
+
1
)
x
n
+
n
.
x
n
+
1
(
1
+
x
)
2
4
)
(
n
-
1
)
x
n
(
1
+
x
)
2
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 26/10/17
F
o
r
a
n
y
n
∈
N
,
t
h
e
v
a
l
u
e
o
f
t
h
e
e
x
p
r
e
s
s
i
o
n
2
+
2
+
2
+
.
.
.
n
t
i
m
e
s
i
s
1
)
2
cos
π
2
n
+
1
2
)
2
sin
π
2
n
+
1
3
)
2
cos
2
n
+
1
π
4
)
2
cos
(
2
n
π
)
Answer
1
Chharishma.r.nayaka
Subject: Maths
, asked on 26/10/17
5
.
∑
k
=
1
n
k
(
1
+
1
n
)
k
-
1
(
i
)
n
(
n
-
1
)
(
i
i
)
n
(
n
+
1
)
(
i
i
i
)
n
2
(
i
v
)
(
n
+
1
)
2
Answer
1
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What are you looking for?
23. If S1={2}, S2={3,6}, S3={4,8,16}, S4={5,10,20,40},..... then the sum of numbers in the set S15 is .
1) 5(215) 2) 16(215-1)
3) 16 (216-1) 4) 15(515-1)
Q.19.
Q.3.
1) n (n - 1)
2) n (n + 1)
3)
4)