UP TGT Mathematics Real Analysis Test Series - Part 2
Is the condition |a_(n+1) - a_n| -> 0 as n -> infinity SUFFICIENT for a sequence to be Cauchy?
Type: MCQ • Marks: 1
Is the condition |a_(n+1) - a_n| -> 0 as n -> infinity SUFFICIENT for a sequence to be Cauchy?
Options
A. Yes, always sufficient
B. Yes, if positive
C. No, counterexample a_n = 1 + 1/2 + ... + 1/n
D. Yes, for all real sequences
Explanation
Correct Answer: Option 3 (No, counterexample a_n = 1 + 1/2 + ... + 1/n). Cauchy General Principle: In R, a sequence converges if and only if it is a Cauchy sequence (|a_n - a_m| < epsilon for n, m >= N). Every Cauchy sequence in R is bounded and convergent.
Want to attempt the full test series with a timer and instant score? Purchase the package to unlock the complete test.
Purchase Now
UP TGTMathematics
Practice more
This page is indexed for search so students can find questions directly from Google.