∫Calc Practice

Integral of \( \displaystyle \sin^{2}{\left(x + 1 \right)} \)

Problem 4.219 · easy

Find \( \displaystyle \int \sin^{2}{\left(x + 1 \right)} \, dx \). (Omit the constant of integration.)
  1. \[ \int \sin^{2}{\left(x + 1 \right)}\, dx \]
    integralStart with the integral of the given function.✓ Proved
  2. \[ = \int \left(\frac{1}{2} - \frac{\cos{\left(2 x + 2 \right)}}{2}\right)\, dx \]
    trig-identityUse the power-reduction identity sin(u)^2 = (1 - cos(2u))/2.✓ Proved
  3. \[ = \int \frac{1}{2}\, dx - \int \frac{\cos{\left(2 x + 2 \right)}}{2}\, dx \]
    linearitySplit the integral into two parts.✓ Proved
  4. \[ = \frac{x}{2} - \int \frac{\cos{\left(2 x + 2 \right)}}{2}\, dx \]
    antiderivativeIntegrate the first term.✓ Proved
  5. \[ = \frac{x}{2} - \frac{\sin{\left(2 x + 2 \right)}}{4} \]
    antiderivativeIntegrate the second term using the substitution rule for cos(ax+b).✓ Proved
Answer \( \frac{x}{2} - \frac{\sin{\left(2 x + 2 \right)}}{4} + C \)

✓ Nihil obstat Every line of this solution was proved by the computer algebra system SymPy. 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
1✓ Provedsympy 1.14.0line 1 is the problem as stated
2✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
3✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
4✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
5✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
answer✓ Provedsympy 1.14.0final line against the stated answer: simplify(a - b) reduced to 0
answer, a second way✓ Provedsympy 1.14.0SymPy differentiated the stated antiderivative back to the integrand

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly applies the power-reduction identity, linearity, and antiderivative rules. Each step changes only one aspect of the expression and uses valid labels from the fixed vocabulary.
Every verdict on record (4)
  • qwen3.6:27b-mlx: pass 2026-10-03 — The solution correctly applies the power-reduction identity, linearity, and antiderivative rules. Each step changes only one aspect of the expression and uses valid labels from the fixed vocabulary.
  • gpt-oss:20b: pass 2026-10-03
  • qwen3.6:27b-mlx: pass 2026-10-03 — The solution correctly applies the power-reduction identity, linearity, and standard antiderivatives. Each step changes only one aspect of the expression and uses valid labels from the fixed vocabulary.
  • gpt-oss:20b: pass 2026-10-03

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 gemma4:26b, checked 2026-10-03 with SymPy 1.14.0.