∫Calc Practice

Derivatives and integrals of hyperbolic functions

Problem 2.2511 · medium

Find \( \displaystyle \int - \sinh{\left(2 x + 3 \right)} \, dx \). (Omit the constant of integration.)
  1. Use (cosh u)′ = sinh u, (sinh u)′ = cosh u, (tanh u)′ = sech²u, with a substitution for the inside.
    Reviewed
  2. \[ \frac{d}{d x} \left(- \frac{\cosh{\left(2 x + 3 \right)}}{2}\right) = - \sinh{\left(2 x + 3 \right)} \]
    Differentiating the answer returns the integrand.✓ Proved
Answer \( - \frac{\cosh{\left(2 x + 3 \right)}}{2} + C \)

✓ 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. How we verify

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 1.3.0a central difference, with sinh and cosh computed from exponentials by mpmath

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly identifies the antiderivative and verifies it via differentiation. The stated answer includes the constant of integration, which is standard practice even if the prompt asks to omit it (as the prompt likely refers to not needing to solve for a specific C, or the checker ignores it). The logic is sound.
Every verdict on record (6)
  • qwen3.6:27b-mlx: pass 2026-10-28 — The solution correctly identifies the antiderivative and verifies it via differentiation. The stated answer includes the constant of integration, which is standard practice even if the prompt asks to omit it (as the prompt likely refers to not needing to solve for a specific C, or the checker ignores it). The logic is sound.
  • gpt-oss:20b: pass 2026-10-28
  • qwen3.6:27b-mlx: pass 2026-10-27 — The solution correctly identifies the antiderivative and verifies it via differentiation. The reference to tanh is irrelevant but harmless.
  • gpt-oss:20b: pass 2026-10-27
  • qwen3.6:27b-mlx: pass 2026-10-27 — The solution correctly identifies the antiderivative and verifies it by differentiation. The reference to standard hyperbolic derivatives is accurate.
  • gpt-oss:20b: pass 2026-10-27

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/hyperbolic_calculus, checked 2026-10-28 with SymPy 1.14.0.