English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

Determine if series is convergent or Diverget. If convergent, find sum.

∑ ((3/5^n) + (2/n))
n=1

The problem is 34 in 12.2 (page 756) in Calculus Stewart 5th edition
Thanks for any help!

2007-04-07 11:31:15 · 3 answers · asked by drsayre2002 3 in Science & Mathematics Mathematics

3 answers

It is divergent.

Note that ((3/5^n)+(2/n)) >1/n for all positive integer n. Then since the series 1/n is divergent (the harmonic series - can be shown to diverge through the integral test), your series is then divergent by the direct comparison test.

Hope that helps!

2007-04-07 11:39:35 · answer #1 · answered by Global_Investor 3 · 0 0

divergent becuase of the 2/n part

you can prove it yourself by adding separately
1/2 1/3+1/4>2/4 1/5+1/6+1/7+1/8>4/8
every group of 2^n terms is more than 1/2 so it must diverge

2007-04-07 11:35:21 · answer #2 · answered by hustolemyname 6 · 0 0

the first summand is a term of a geometric series with r=1/5 convergent,but the second is 2(1/n) which is a term of the harmonic series divergent.So the series is divergent

2007-04-07 11:36:15 · answer #3 · answered by santmann2002 7 · 0 0

fedest.com, questions and answers