Problem Analysis #29

139.32s
26,343 toks
Problem Statement

Consider the point A(2,0)A(-2,0) in the coordinate plane. Suppose two points PP and QQ satisfy the following conditions:

  • [(i)] The vectors AP\overrightarrow{AP} and AQ\overrightarrow{AQ} are parallel.
  • [(ii)] The dot product satisfies APAQ=9\overrightarrow{AP} \cdot \overrightarrow{AQ} = 9. Let the two circlesC1:x2+y2=1,\qquadC2:(x+1)2+y2=1C_{1} : x^{2} + y^{2} = 1, \qquadC_{2} : (x+1)^{2} + y^{2} = 1intersect at two distinct points R1R_{1} and R2R_{2}.Consider the region R\mathcal{R} consisting of the arc R1OR2R_{1}O'R_{2} of circle C1C_{1},which contains the point O(1,0)O'(-1,0), together with the arc R1OR2R_{1}OR_{2} of circle C2C_{2},which contains the point O(0,0)O(0,0).When the point PP moves along the region R\mathcal{R}, let kk denote the total lengthof the locus traced by the corresponding point QQ.For any real number ss, let s\lfloor s \rfloor denote the greatest integer less than or equal to ss.Determine the value of k\lfloor k \rfloor.
Ground Truth
17
Execution Trace
Reasoning Process

The locus of point (Q) is traced as (P) moves along the region (\mathcal{R}), which consists of two arcs: the arc (R_1O'R_2) on circle (C_1) and the arc (R_1OR_2) on circle (C_2).

For (P) on the arc (R_1O'R_2) of (C_1) (parameterized by (\theta) from (120^\circ) to (240^\circ)), the locus of (Q) is an arc of the circle ((x-4)^2 + y^2 = 9). The arc length is (6\pi\sqrt{3}).

For (P) on the arc (R_1OR_2) of (C_2) (parameterized by (\phi) from (60^\circ) to (-60^\circ)), the locus of (Q) is a vertical line segment at (x = 2.5) from ((2.5, \frac{3\sqrt{3}}{2})) to ((2.5, -\frac{3\sqrt{3}}{2})). The length of this segment is (3\sqrt{3}).

The total length (k) of the locus is the sum of these two lengths: [ k = 6\pi\sqrt{3} + 3\sqrt{3} = 3\sqrt{3}(2\pi + 1). ]

Numerically, (2\pi \approx 6.283185307), so (2\pi + 1 \approx 7.283185307). Then (\sqrt{3} \approx 1.73205080757), so (3\sqrt{3} \approx 5.19615242271). Thus, [ k \approx 5.19615242271 \times 7.283185307 \approx 37.84454. ]

The floor of (k) is (\lfloor k \rfloor = 37).

\boxed{37}

Reasoning Process

[THOUGHT] We need to compute the total length k using Python to get the numerical value and then take the floor. [/THOUGHT] [PYTHON] import math k = 3 * math.sqrt(3) * (2 * math.pi + 1) k_floor = math.floor(k) print(k_floor) [/PYTHON]

Tool Output
[PYTHON OUTPUT] 37 [/PYTHON OUTPUT]
Reasoning Process

\boxed{37}

Final Model Output
37

Comparative Analysis (P29) (Average across runs)

Avg Time Taken

K-EXAONE-236B-A23B
946.4
EXAONE-4.0.1-32B (high)
298.6
GPT-5.1 (high)
227.4
Gemini-3-Pro-Preview
139.0
Solar-Open-100B
118.5
Deepseek-V3.2
109.1
Kanana-2-30B-Thinking-2601
95.8
Llama-VARCO-8B-Instruct
74.3
Kanana-2-30B-Thinking
73.3
K-EXAONE-236B-A23B
72.2
Solar-Pro-2 (31B)(high)
67.2
GPT-5.2 (high)
64.2
Grok-4.1-fast
38.9
Claude-Opus-4.5
38.3
HCX-007(high)
28.4
A.X-4.0 (72B)
21.1
axk1
7.2

Avg Token Usage

K-EXAONE-236B-A23B
79802.0
Solar-Open-100B
19908.0
Kanana-2-30B-Thinking-2601
19089.0
GPT-5.1 (high)
14833.0
Kanana-2-30B-Thinking
12633.0
Claude-Opus-4.5
11516.0
K-EXAONE-236B-A23B
10828.0
Solar-Pro-2 (31B)(high)
10423.0
Grok-4.1-fast
9673.0
Deepseek-V3.2
8977.0
Gemini-3-Pro-Preview
8560.0
GPT-5.2 (high)
8089.0
EXAONE-4.0.1-32B (high)
6140.0
Llama-VARCO-8B-Instruct
5349.0
HCX-007(high)
4304.0
axk1
3143.0
A.X-4.0 (72B)
2252.0