Convergence Test for Series with Square Root Terms

Click For Summary
SUMMARY

The forum discussion focuses on determining the convergence or divergence of the series (summation n=1 to infinity) sqrt(n+2)/(2n^2+n+1) using the Comparison Test and Limit Comparison Test (LCT). The initial comparison with sqrt(x)/2n^2, which simplifies to 1/2n^(3/2), led to confusion due to an inequality reversal when substituting values. Participants suggest alternative comparisons, such as sqrt(n+n)/(2n^2), to effectively analyze the series' behavior.

PREREQUISITES
  • Understanding of the Comparison Test in series convergence
  • Familiarity with the Limit Comparison Test (LCT)
  • Knowledge of series involving square root terms
  • Basic algebraic manipulation of inequalities
NEXT STEPS
  • Study the Comparison Test for series convergence in detail
  • Learn about the Limit Comparison Test (LCT) and its applications
  • Explore examples of series with square root terms for better understanding
  • Practice algebraic techniques for manipulating inequalities in series
USEFUL FOR

Students studying calculus, particularly those focusing on series convergence, as well as educators and tutors looking for effective teaching strategies in this area.

lha08
Messages
158
Reaction score
0

Homework Statement


Using Comparison test and LCT, determine whether it is convergent or divergent:

(summation n=1 to infinity) sqrt(n+2)/(2n^2+n+1)



Homework Equations





The Attempt at a Solution


i compared it with sqrt(x)/2n^2 which is 1/2n^(3/2)
and then the answer showed something weird...they had to plug in a number (e.g. 1) which reversed the inequality sign... to sqrt(n+2)/(2n^2+n+1) is larger than 1/2n^(3/2)...does anyone know why?
 
Physics news on Phys.org


Then pick a different comparison. You want to make the numerator larger and the denominator smaller if you think it converges. Be creative! How about comparing with sqrt(n+n)/(2n^2)?
 

Similar threads

Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
7
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K