Problem Analysis #0

17.02s
5,244 toks
Problem Statement

Consider the curve CC given in polar coordinates byr=2+cosθ(0θ2π),r = 2 + \cos\theta \qquad (0 \le \theta \le 2\pi),with the origin OO as the pole and the positive xx–axis as the initial line.

  • [(1)] Compute the area of the region enclosed by the curve CC.
  • [(2)] At the point (r,θ)=(4+22,π4), (r,\theta)=\left(\frac{4+\sqrt{2}}{2},\,\frac{\pi}{4}\right), find the slope of the tangent line to the curve CC in the xyxy–coordinate plane. Let aa be the value obtained in part (1). Express the answer from part (2) in the formb+c,b + \sqrt{c},where bb and cc are integers, and let those integers be the definitions of bb and cc. Using these values of aa, bb, and cc, computeabcπ.\frac{abc}{\pi}.\
Ground Truth
-18
Execution Trace
Reasoning Process

[THOUGHT] I will compute the area enclosed by the polar curve r = 2 + cosθ using the polar area formula A = ½∫₀^{2π} r² dθ. Then I will find the slope dy/dx at θ = π/4 using the polar derivative formulas: dx/dθ = dr/dθ·cosθ − r·sinθ, dy/dθ = dr/dθ·sinθ + r·cosθ, with dr/dθ = −sinθ. I will simplify the resulting expression to the form b + √c. Finally, I will compute abc/π where a = area, b and c are the integers from the slope expression. [/THOUGHT] [PYTHON] import sympy as sp

Define theta

theta = sp.symbols('theta', real=True)

Part (1): Area

r = 2 + sp.cos(theta) area = sp.Rational(1,2) * sp.integrate(r**2, (theta, 0, 2*sp.pi)) area_simplified = sp.simplify(area)

Part (2): Slope dy/dx

dr_dtheta = sp.diff(r, theta) # -sin(theta) dx_dtheta = dr_dtheta * sp.cos(theta) - r * sp.sin(theta) dy_dtheta = dr_dtheta * sp.sin(theta) + r * sp.cos(theta) slope = sp.simplify(dy_dtheta / dx_dtheta)

Evaluate at theta = pi/4

theta_val = sp.pi/4 r_val = r.subs(theta, theta_val) slope_at_point = sp.simplify(slope.subs(theta, theta_val))

Express slope as b + sqrt(c)

Extract b and c

b = sp.nsimplify(slope_at_point - sp.sqrt(slope_at_point2 - sp.simplify(slope_at_point2 - sp.simplify(slope_at_point**2)))) # placeholder, we will manually identify

Instead, we can match pattern b + sqrt(c)

Use sp.collect to see if sqrt term present

collected = sp.collect(slope_at_point, sp.sqrt(2), evaluate=False)

Since sqrt(2) appears, we can write slope = b + sqrt(c)

Let's solve for b and c

slope = b + sqrt(c)

We know slope = sqrt(2) - 2, so b = -2, c = 2

b_val = -2 c_val = 2

Compute abc/pi

abc_over_pi = (area_simplified * b_val * c_val) / sp.pi

Print results

print("Area a:", area_simplified) print("Slope at theta=pi/4:", slope_at_point) print("b:", b_val) print("c:", c_val) print("abc/pi:", abc_over_pi) [/PYTHON]

Tool Output
[PYTHON OUTPUT] Area a: 9*pi/2 Slope at theta=pi/4: -2 + sqrt(2) b: -2 c: 2 abc/pi: -18 [/PYTHON OUTPUT]
Reasoning Process

[THOUGHT] The Python output provides the exact values: area ( a = \frac{9\pi}{2} ), slope expression ( b = -2 ), ( c = 2 ), and ( \frac{abc}{\pi} = -18 ). The calculation confirms this result. [/THOUGHT] \boxed{-18}

Final Model Output
-18

Comparative Analysis (P0) (Average across runs)

Avg Time Taken

Gemini-3-Pro-Preview
316.3
K-EXAONE-236B-A23B
234.2
Deepseek-V3.2
81.3
Kanana-2-30B-Thinking
70.7
Kanana-2-30B-Thinking-2601
59.2
Llama-VARCO-8B-Instruct
49.3
GPT-5.1 (high)
38.4
HCX-007(high)
36.4
GPT-5.2 (high)
33.6
Solar-Pro-2 (31B)(high)
30.2
K-EXAONE-236B-A23B
21.4
Grok-4.1-fast
21.1
Claude-Opus-4.5
18.0
Solar-Open-100B
17.0
A.X-4.0 (72B)
16.6
axk1
7.6
EXAONE-4.0.1-32B (high)
6.7

Avg Token Usage

K-EXAONE-236B-A23B
22900.7
Gemini-3-Pro-Preview
12238.0
Kanana-2-30B-Thinking-2601
12235.0
Kanana-2-30B-Thinking
12196.0
Deepseek-V3.2
7244.0
GPT-5.2 (high)
7100.0
Solar-Pro-2 (31B)(high)
6632.0
K-EXAONE-236B-A23B
6596.0
HCX-007(high)
6397.0
Grok-4.1-fast
6290.0
Solar-Open-100B
5244.0
GPT-5.1 (high)
4822.0
Claude-Opus-4.5
4528.0
Llama-VARCO-8B-Instruct
4316.0
EXAONE-4.0.1-32B (high)
4306.0
A.X-4.0 (72B)
3605.0
axk1
3010.0