∫Calc Practice

Converting between polar and rectangular coordinates

Problem 8.114 · easy

Convert the rectangular point \( \displaystyle \left(0, 2\right) \) to polar coordinates with \( \displaystyle r > 0 \) and \( \displaystyle 0 \le \theta < 2\pi \).
  1. \[ 2 \]
    r = √(x² + y²).✓ Proved
  2. The point is in an axis direction; θ = pi/2.
    Reviewed
  3. \[ \left[\begin{matrix}0\\2\end{matrix}\right] \]
    Converting back gives the point.✓ Proved
Answer \( \left(2, \frac{\pi}{2}\right) \)

✓ Nihil obstat Lines: 2 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
1✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
2Reviewedreviewers: gpt-oss:20b, qwen3.6:27b-mlxa sentence; read, not computed
3✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
answer, a second way✓ Checked independentlysympy 1.14.0 + mpmath 1.3.0r and θ from hypot and atan2

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly identifies the radius and angle for the point (0, 2) and verifies the conversion. The reasoning is sound and concise.
Every verdict on record (4)
  • qwen3.6:27b-mlx: pass 2026-10-05 — The solution correctly identifies the radius and angle for the point (0, 2) and verifies the conversion. The reasoning is sound and concise.
  • gpt-oss:20b: pass 2026-10-05
  • qwen3.6:27b-mlx: pass 2026-10-05 — The solution correctly identifies the radius and angle for the point (0, 2) and verifies the conversion.
  • gpt-oss:20b: pass 2026-10-05

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/polar_conversion, checked 2026-10-05 with SymPy 1.14.0.