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If
lim
x
→
1
x
+
x
2
+
x
3
+
⋯
+
x
n
−
n
x
−
1
=
820
,
(
n
∈
N
)
\lim_{x \rightarrow 1} \frac{x + x^2 + x^3 + \dots + x^n - n}{x - 1} = 820, (n \in N)
lim
x
→
1
x
−
1
x
+
x
2
+
x
3
+
⋯
+
x
n
−
n
=
820
,
(
n
∈
N
)
…
Mathematics
Problem
If
lim
x
→
1
x
+
x
2
+
x
3
+
⋯
+
x
n
−
n
x
−
1
=
820
,
(
n
∈
N
)
\lim_{x \rightarrow 1} \frac{x + x^2 + x^3 + \dots + x^n - n}{x - 1} = 820, (n \in N)
lim
x
→
1
x
−
1
x
+
x
2
+
x
3
+
⋯
+
x
n
−
n
=
820
,
(
n
∈
N
)
then the value of
n
n
n
is equal to (a) 40 (b) 41 (c) 50 (d) 100
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