Squeeze theorem

If a sequence is trapped between two sequences that both converge to the same limit L, then the trapped sequence also converges to L. It is used to find limits that are hard to compute directly by bounding them above and below.

\lim_{n\to\infty}a_n=\lim_{n\to\infty}c_n=L \land a_n\le b_n\le c_n \implies \lim_{n\to\infty}b_n=L

What the symbols mean

lower bounding sequence
sequence trapped between the bounds
upper bounding sequence
common limit of the bounding sequences
index of the sequence, tending to infinity

About this formula

  • FieldMathematics
  • TopicLimits
  • LevelHigh school
  • Also calledpinching theorem, sandwich theorem, sandwich rule, squeeze lemma, limit sandwich theorem, squeeze theorem for sequences
  • SourceWikidata Q1065257

Write it in Obsidian

MathLive is a free visual math editor for Obsidian. Run Find a formula, type “squeeze theorem”, and it goes into your note as editable LaTeX. You can also scan formulas from screenshots, PDFs and handwriting.

Related formulas