∫Calc Practice

Differential equations by direct integration

Problem 6.532 · easy

Solve \( \displaystyle y' = 3 x + e^{x} \) with \( \displaystyle y(0) = 3 \).
  1. \[ \frac{d}{d x} \left(\frac{3 x^{2}}{2} + e^{x}\right) = 3 x + e^{x} \]
    Integrate: y = this + C.✓ Proved
  2. \[ 3 - \left. \frac{3 x^{2}}{2} + e^{x} \right|_{\substack{ x=0 }} = 2 \]
    y(0) = 3 fixes C.✓ Proved
  3. \[ \left. \frac{3 x^{2}}{2} + e^{x} + 2 \right|_{\substack{ x=0 }} = 3 \]
    The initial condition holds.✓ Proved
Answer \( y = \frac{3 x^{2}}{2} + e^{x} + 2 \)

✓ 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. How we verify

The full receipt
LineStatusChecked byDetail
1✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
2✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
3✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
answer, a second way✓ Checked independentlysympy 1.14.0 + mpmath 1.3.0finite differences of the answer match f, and the initial value holds

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly identifies the general antiderivative, determines the constant of integration using the initial condition, and verifies the result.
Every verdict on record (6)
  • qwen3.6:27b-mlx: pass 2026-10-18 — The solution correctly identifies the general antiderivative, determines the constant of integration using the initial condition, and verifies the result.
  • gpt-oss:20b: pass 2026-10-18
  • qwen3.6:27b-mlx: pass 2026-10-15 — The solution correctly identifies the general antiderivative, determines the constant of integration using the initial condition, and verifies the result. The logic is sound.
  • gpt-oss:20b: pass 2026-10-15
  • qwen3.6:27b-mlx: pass 2026-10-14 — The solution correctly identifies the general antiderivative, determines the constant of integration using the initial condition, and verifies the final result.
  • gpt-oss:20b: pass 2026-10-14

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/de_direct_integration, checked 2026-10-18 with SymPy 1.14.0.