Consider the series
\sum_(n=1)^(\infty ) (n)/((n+1)!)
. (a) Find the partial sums
s_(1),s_(2),s_(3)
, and
s_(4)
. Do you recognize the denominators?
s_(1)=
s_(2)=
s_(3)=
s_(4)=
Use the pattern to guess a formula for
s_(n)
.
s_(n)=((n+1)!+1)/((n+1)!)
s_(n)=((n+1)!-1)/(n!)
s_(n)=(n!-1)/(n!)
s_(n)=((n+1)!-1)/((n+1)!)
s_(n)=((n-1)!-1)/((n-1)!)
Test the series for convergence or divergence using the Alternating Series Test.
\sum_(n=1)^(\infty ) ((-1)^(n-1))/(7+8n)
Identify
b_(n)
.
(1+(-1)^(n))/(\sqrt(n)+4)
Evaluate the following limit.
\lim_(n->\infty )b_(n)
Since
\lim_(n->\infty )b_(n)=hat(?),0
and
b_(n+1)<=hat(?)b_(n)
for all
n
, Test the series for convergence or divergence using the Alternating Series Test.
\sum_(n=0)^(\infty ) ((-1)^(n+1))/(\sqrt(n+4))
Identify
b_(n)
.
(1+(-1)^(n))/(\sqrt(n)+4)
Evaluate the following limit.
\lim_(n->\infty )b_(n)
Since
\lim_(n->\infty )b_(n)=hat(?),0
and
b_(n+1)<=hat(v)b_(n)
for all
n
,