Answer:
Radius of the convergence is R = 
and,
The Interval of convergence is 
Step-by-step explanation:
Given function : Σ(21x)^k
Now,
Using the ratio test, we have
R = 
or
R = 
or
R = 
now,
for convergence R|x| < 1
Therefore,
< 1
or

and,
Radius of the convergence is R = 
and,
The Interval of convergence is 
The answer is D!
hopefully this helps
Answer:
x=2 2/3
Step-by-step explanation:
The equation also means that x=8^3
8/3=2 2/3
The length I think is 15 and the width I think is 19
There are 13 spades. 1/13
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