Fraction Limit Calculator — Evaluate Limits of Rational Functions

Fraction Limit Calculator

Calculate the limit of a rational function (fraction) as x approaches any value. Understand limits step by step with our free tool.

Step 1: Define f(x) = (Ax + B) / (Cx + D)

Rational function limit

For linear/linear fractions, the limit as x→a is computed by substitution. If 0/0 occurs, the limit equals A/C (derivative ratio).

Step 2: Limit options

1.0

Classic limits

sin(x)/x → 1 (x→0)   (1-cos(x))/x → 0   (eˣ-1)/x → 1

Limit Result

Summary
Classic Limits
Explanation

Limit of f(x) as x → 1.0

2.00
(2x+2)/(x+1) simplifies to 2
Numerator at x = a
4.0
Denominator at x = a
2.0
Direct substitution
2.0
Limit interpretation
Removable? No

Classic Limits Comparison

Limit expression Value

How the limit is computed

For f(x) = (Ax + B) / (Cx + D) as x → a

1. Substitute x = a into numerator and denominator.
2. If denominator ≠ 0, limit = (A·a + B) / (C·a + D).
3. If denominator = 0 and numerator ≠ 0, the limit is infinite (sign depends on direction).
4. If both are 0, we have an indeterminate 0/0. For linear numerator/denominator, the limit equals A / C (derivatives).

Example: (2x+2)/(x+1) as x→ -1 gives 0/0 → limit = 2/1 = 2.

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