∫Calc Practice

Limit laws with given limits

Problem 1.337 · easy

Suppose \( \displaystyle \lim_{x\to -2} f(x) = 5 \), \( \displaystyle \lim_{x\to -2} g(x) = 2 \) and \( \displaystyle \lim_{x\to -2} h(x) = 6 \). Find \( \displaystyle \lim_{x\to -2} \left(\frac{f(x)}{g(x) + h(x)}\right) \).
  1. Each piece has a finite limit, and no denominator's limit is 0, so the limit laws (quotient of a sum) let us replace every function by its limit.
    Reviewed
  2. \[ \frac{5}{2 + 6} = \frac{5}{8} \]
    Substitute the three limits and simplify.✓ Proved
Answer \( \frac{5}{8} \)

✓ Nihil obstat Lines: 1 proved, 1 reviewed. The answer was also checked a second way, without looking at the solution. Reviewers found nothing wrong with the explanation.

The full receipt
LineStatusChecked byDetail
1Reviewedreviewers: gpt-oss:20b, qwen3.6:27b-mlxa sentence; read, not computed
2✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
answer, a second way✓ Checked independentlysympy 1.14.0 + mpmath 1.3.0the limit of the same combination of concrete functions with those limits, taken by SymPy

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly identifies the applicability of limit laws (quotient and sum) given that the denominator's limit is non-zero. The calculation is correct.
Every verdict on record (4)
  • gpt-oss:20b: pass 2026-10-06
  • qwen3.6:27b-mlx: pass 2026-10-06 — The solution correctly identifies the applicability of limit laws (quotient and sum) given that the denominator's limit is non-zero. The calculation is correct.
  • gpt-oss:20b: pass 2026-10-06
  • qwen3.6:27b-mlx: pass 2026-10-06 — The solution correctly applies the limit laws for quotients and sums, verifying that the denominator's limit is non-zero.

Proved: SymPy reduced the difference between the two sides to zero. Checked independently: a separate method, named above, confirmed it. Checked numerically: the two sides agree at every sampled point, which is evidence, not proof. Reviewed: a model or a person read it; that is all a sentence can have. Solution by generator:structured/limit_laws_values, checked 2026-10-06 with SymPy 1.14.0.