Problem Analysis #20

EXAONE-4.0.1-32B (high) · Run 1

7.57s
5,036 toks
Problem Statement

Let a function f(x)f(x) defined on the set of all real numbers satisfy

f(x)=xsin(πx)for x[0,2],f(x) = x \sin(\pi x) \qquad \text{for } x \in [0,2],

and

f(x)=2f(x2)for all real x.f(x) = 2 f(x-2) \qquad \text{for all real } x.

Consider the region enclosed by the curve y=f(x)y = f(x), the line

y=21012(x2026),y = 2^{1012}(x - 2026),

and the two vertical lines x=2026x = 2026 and x=2027x = 2027.The area of this region is equal to

21012(p+qπ+r3π),2^{1012}\left(p + \frac{q}{\pi} + \frac{r\sqrt{3}}{\pi}\right),

for some rational numbers p,q,rp, q, r.Find the value of 2028pqr2028 \cdot p \cdot q \cdot r.oindent

Ground Truth
1352
Execution Trace
Reasoning Process

[THOUGHT] To solve this problem, we need to find the area of the region enclosed by the curve y=f(x)y = f(x), the line y=21012(x2026)y = 2^{1012}(x - 2026), and the vertical lines x=2026x = 2026 and x=2027x = 2027.

  1. Understand the function f(x)f(x):

    • For x[0,2]x \in [0, 2], f(x)=xsin(πx)f(x) = x \sin(\pi x).
    • For other xx, f(x)=2f(x2)f(x) = 2 f(x-2). This means f(x)f(x) is defined recursively, scaling by 2 every 2 units.
  2. Find f(x)f(x) for x[2026,2027]x \in [2026, 2027]:

    • Since f(x)f(x) is defined recursively, we can express f(x)f(x) in terms of f(x2k)f(x - 2k) where x2k[0,2]x - 2k \in [0, 2].
    • For x[2026,2027]x \in [2026, 2027], let x=2026+tx = 2026 + t where t[0,1]t \in [0, 1].
    • Then, x2×1013=2026+t2026=tx - 2 \times 1013 = 2026 + t - 2026 = t, so f(x)=21013f(t)=21013tsin(πt)f(x) = 2^{1013} f(t) = 2^{1013} t \sin(\pi t).
  3. Set up the integral for the area:

    • The area is the integral of the difference between the line and the curve from x=2026x = 2026 to x=2027x = 2027.
    • The line is y=21012(x2026)=21012ty = 2^{1012}(x - 2026) = 2^{1012} t (where t=x2026t = x - 2026).
    • The curve is y=21013tsin(πt)y = 2^{1013} t \sin(\pi t).
    • The difference is 21012t21013tsin(πt)=21012t(12sin(πt))2^{1012} t - 2^{1013} t \sin(\pi t) = 2^{1012} t (1 - 2 \sin(\pi t)).
  4. Compute the integral:

    • The area AA is:
A=0121012t(12sin(πt))dtA = \int_{0}^{1} 2^{1012} t (1 - 2 \sin(\pi t)) \, dt
  • This can be split into two integrals:
A=21012(01tdt201tsin(πt)dt)A = 2^{1012} \left( \int_{0}^{1} t \, dt - 2 \int_{0}^{1} t \sin(\pi t) \, dt \right)
  • The first integral is straightforward:
01tdt=12\int_{0}^{1} t \, dt = \frac{1}{2}
  • The second integral requires integration by parts:
tsin(πt)dt=tcos(πt)π+sin(πt)π2+C\int t \sin(\pi t) \, dt = -\frac{t \cos(\pi t)}{\pi} + \frac{\sin(\pi t)}{\pi^2} + C
 Evaluating from 0 to 1:
 
tcos(πt)π+sin(πt)π201=cos(π)π+sin(π)π20=1π\left. -\frac{t \cos(\pi t)}{\pi} + \frac{\sin(\pi t)}{\pi^2} \right|_{0}^{1} = -\frac{\cos(\pi)}{\pi} + \frac{\sin(\pi)}{\pi^2} - 0 = \frac{1}{\pi}
  • Thus:
A=21012(1221π)=21012(122π)A = 2^{1012} \left( \frac{1}{2} - 2 \cdot \frac{1}{\pi} \right) = 2^{1012} \left( \frac{1}{2} - \frac{2}{\pi} \right)
  • However, the problem states the area is of the form 21012(p+qπ+r3π)2^{1012} \left( p + \frac{q}{\pi} + \frac{r \sqrt{3}}{\pi} \right). Comparing, we see p=12p = \frac{1}{2}, q=2q = -2, and r=0r = 0.
  1. Compute 2028pqr2028 \cdot p \cdot q \cdot r:
    • Since r=0r = 0, the product 2028pqr=02028 \cdot p \cdot q \cdot r = 0.

[/THOUGHT] [PYTHON]

Verify the integral calculations

from sympy import symbols, integrate, sin, pi

t = symbols('t') integral1 = integrate(t, (t, 0, 1)) # Should be 1/2 integral2 = integrate(t * sin(pi * t), (t, 0, 1)) # Should be 1/pi

print(integral1, integral2) [/PYTHON]

Tool Output
[PYTHON OUTPUT] 1/2 1/pi [/PYTHON OUTPUT]
Reasoning Process

[THOUGHT] The Python output confirms the integral calculations:

  • 01tdt=12\int_{0}^{1} t \, dt = \frac{1}{2}
  • 01tsin(πt)dt=1π\int_{0}^{1} t \sin(\pi t) \, dt = \frac{1}{\pi}

Thus, the area is:

A=21012(122π)A = 2^{1012} \left( \frac{1}{2} - \frac{2}{\pi} \right)

This matches the form 21012(p+qπ+r3π)2^{1012} \left( p + \frac{q}{\pi} + \frac{r \sqrt{3}}{\pi} \right) with p=12p = \frac{1}{2}, q=2q = -2, and r=0r = 0. Therefore, 2028pqr=02028 \cdot p \cdot q \cdot r = 0.

[/THOUGHT] 0\boxed{0}

Final Model Output
0

Comparative Analysis (P20) (Average across runs)

Avg Time Taken

K-EXAONE-236B-A23B
1117.7
Solar-Open-100B
743.0
Solar-Pro-2 (31B)(high)
209.1
Llama-VARCO-8B-Instruct
194.6
Gemini-3-Pro-Preview
117.1
A.X-4.0 (72B)
98.1
Grok-4.1-fast
91.6
Kanana-2-30B-Thinking
82.5
HCX-007(high)
65.9
K-EXAONE-236B-A23B
64.2
GPT-5.1 (high)
59.3
Deepseek-V3.2
40.9
Kanana-2-30B-Thinking-2601
39.3
Claude-Opus-4.5
27.1
GPT-5.2 (high)
22.2
EXAONE-4.0.1-32B (high)
7.6

Avg Token Usage

K-EXAONE-236B-A23B
231,341
Solar-Open-100B
23,307
Kanana-2-30B-Thinking
15,652
Grok-4.1-fast
15,328
Gemini-3-Pro-Preview
13,814
Solar-Pro-2 (31B)(high)
12,507
Kanana-2-30B-Thinking-2601
9,180
HCX-007(high)
7,833
GPT-5.1 (high)
7,486
Deepseek-V3.2
7,264
Llama-VARCO-8B-Instruct
7,065
K-EXAONE-236B-A23B
6,115
GPT-5.2 (high)
5,568
Claude-Opus-4.5
5,400
EXAONE-4.0.1-32B (high)
5,036
A.X-4.0 (72B)
3,005