∫Calc Practice

Differential equations by direct integration

Problem 6.740 · easy

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

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. The reviewers disagree about how one step is explained; every verdict is in the receipt. 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 antiderivative and determines the constant of integration using the initial condition. The logic is sound and the steps are valid.
Every verdict on record (6)
  • qwen3.6:27b-mlx: pass 2026-10-26 — The solution correctly identifies the antiderivative and determines the constant of integration using the initial condition. The logic is sound and the steps are valid.
  • gpt-oss:20b: pass 2026-10-26
  • qwen3.6:27b-mlx: pass 2026-10-25 — The solution correctly identifies the antiderivative and applies the initial condition to determine the constant of integration. The steps are logically sound and algebraically verified.
  • gpt-oss:20b: pass 2026-10-25
  • qwen3.6:27b-mlx: fail (error) 2026-10-25 — The solution fails to explicitly state the general solution y = e^{x^2} + C before applying the initial condition. It jumps from recognizing the derivative to checking the final answer, omitting the crucial step of determining the constant of integration C = -1.
  • gpt-oss:20b: pass 2026-10-25

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 2026-10-26 with SymPy 1.14.0.