Two-Sided Inspection

f(x) = (x² - 1)/(x - 1), x ≠ 1
From the leftx = 0.99f(x) = 1.99
From the rightx = 1.01f(x) = 2.01
Value at pointUndefined
Two-sided verdictFinite limit: 2
ClassificationRemovable

Both sides approach 2. Defining f(1)=2 repairs continuity.

Comparison Record

ModelhLeft sampleRight sampleVerdict

Oscillation needs witness sequences

For sin(1/x), ordinary decimal samples can accidentally suggest a pattern. The analytical diagnosis uses sequences approaching zero that force the function to equal 1 and -1 repeatedly. Because those outputs remain separated while both input sequences approach the same point, no limit exists.