Tardigrade
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Tardigrade
Question
Mathematics
Let ln = (2n + (-2)n /2n) and Ln = (2n + (- 2)n/3n) then as n →∞
Q. Let
l
n
=
2
n
2
n
+
(
−
2
)
n
and
L
n
=
3
n
2
n
+
(
−
2
)
n
then as
n
→
∞
1461
219
UPSEE
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A
Both the sequences have limits
0%
B
n
→
∞
lim
l
n
exists but
n
→
∞
lim
L
n
does not exist
38%
C
n
→
∞
lim
l
n
does not exist but
n
→
∞
lim
L
n
exists
25%
D
Both the sequences do not have limits.
38%
Solution:
Given, ln
=
2
n
2
n
+
(
−
2
)
n
=
1
+
2
n
(
−
2
)
n
.
˙
.
(
i
)
And
L
n
=
3
n
2
n
+
(
−
2
)
2
n
...
(
ii
)
Now, from Eq. (i), we get
n
→
∞
lim
ln
=
{
0
,
2
,
when
n
is odd
when
n
is even
∴
n
→
∞
lim
does not exist
and
n
→
∞
lim
L
n
=
0
∴
x
→
∞
lim
L
n
exist.