OPSFT
Collection
12 items • Updated
prompt stringlengths 102 4.77k | response stringlengths 39 65.5k | ground_truth stringlengths 1 44.2M | teacher_verified bool 1
class | source_index int64 0 57k |
|---|---|---|---|---|
Consider a holomorphic homeomorphism $f: U \rightarrow U$ of the unit disc $U$. Must $f$ extend to a continuous map $f: \overline{U} \rightarrow \overline{U}$? Provide a justification for your answer.
Please reason step by step, and put your final answer within \boxed{}. | We are given a **holomorphic homeomorphism** $ f: U \to U $, where $ U = \{ z \in \mathbb{C} : |z| < 1 \} $ is the open unit disc. The question is whether $ f $ **must extend to a continuous map** $ \overline{f}: \overline{U} \to \overline{U} $, where $ \overline{U} $ is the closed unit disc.
Let’s analyze this step b... | Yes | true | 16,456 |
In triangle \(ABC\), let \(\omega\) be the incircle tangent to \(BC, CA,\) and \(AB\) at points \(D, E,\) and \(F\) respectively. A point \(P\) on \(EF\) is such that \(PD\) is perpendicular to \(BC\). The line \(AP\) intersects \(BC\) at \(Q\). Circles \(\omega_1\) and \(\omega_2\) pass through \(B\) and \(C\) respect... | We are given triangle $ABC$ with side lengths:
- $AB = 15$
- $BC = 14$
- $CA = 13$
Let’s solve this step-by-step using geometry, coordinate geometry, and properties of incircles, tangency, and circles.
---
### **Step 1: Coordinates Setup**
We place triangle $ABC$ in the coordinate plane.
Let:
- $B = (0, 0)$
- $C ... | 101 | true | 55,134 |
Determine whether the Galois group of the polynomial \( f(x) = (x^2-ax+b)(x^2-cx+d) \), where \( f(x) \) is a separable polynomial with rational coefficients, is always a subgroup of the Klein four group \( C_2 \times C_2 \).
Please reason step by step, and put your final answer within \boxed{}. | We are given a polynomial
$$
f(x) = (x^2 - ax + b)(x^2 - cx + d),
$$
where $ f(x) $ is **separable** and has **rational coefficients**. We are to determine whether the **Galois group** of $ f(x) $ over $ \mathbb{Q} $ is **always** a subgroup of the **Klein four-group** $ C_2 \times C_2 $.
---
### Step 1: Understand... | Yes | true | 7,223 |
Find all natural numbers \( N > 1 \) such that when all natural divisors of \( N \) are listed in ascending order, the sum of the greatest common divisors of each pair of adjacent divisors equals \( N-2 \).
Please reason step by step, and put your final answer within \boxed{}. | We are given a natural number $ N > 1 $, and we are to **find all such $ N $** such that:
> When all natural divisors of $ N $ are listed in ascending order, the **sum of the GCDs of each pair of adjacent divisors** equals $ N - 2 $.
Let’s denote the divisors of $ N $ in ascending order as:
$$
d_1 = 1 < d_2 < d_3 < \... | 3 | true | 55,997 |
Find the norm of the linear operator $T: C[0,1] \to \mathbb{R}$ defined by $T(f) = \int_0^1 2x f(x) \, dx$, where $C[0,1]$ is the space of continuous functions on the interval $[0,1]$ equipped with the supremum norm.
Please reason step by step, and put your final answer within \boxed{}. | We are given a linear operator $ T: C[0,1] \to \mathbb{R} $ defined by
$$
T(f) = \int_0^1 2x f(x) \, dx,
$$
where $ C[0,1] $ is the space of continuous real-valued functions on $[0,1]$, equipped with the **supremum norm**:
$$
\|f\|_\infty = \sup_{x \in [0,1]} |f(x)|.
$$
We are to compute the **operator norm** of $ ... | 1 | true | 35,875 |
Let $A$ and $B$ be two positive semi-definite $n \times n$ matrices such that \( \mathrm{Range}(B^{1/2}AB^{1/2}) = \mathrm{Range}(B) \) and \( \mathrm{Rank}(A) = \mathrm{Rank}(B) = n-1 \). Determine whether there exists a real symmetric matrix $X$ such that $A = XBX$. Provide a justification for your answer.
Please rea... | We are given:
- $ A $ and $ B $ are $ n \times n $ **positive semi-definite** matrices.
- $ \mathrm{Rank}(A) = \mathrm{Rank}(B) = n - 1 $.
- $ \mathrm{Range}(B^{1/2}AB^{1/2}) = \mathrm{Range}(B) $.
- We are to determine whether there exists a **real symmetric matrix** $ X $ such that:
$$
A = X B X.
$$
We will a... | Yes | true | 10,344 |
Given the group presentation \( \langle x, y \mid x^n = y^2 = 1, xy = yx^2 \rangle \), where \( n = 3k \) for some integer \( k \), determine the order of \( x \). Can the order of \( x \) be concluded to be exactly 3 under this condition?
Please reason step by step, and put your final answer within \boxed{}. | We are given a group presentation:
$$
\langle x, y \mid x^n = y^2 = 1, \, xy = yx^2 \rangle
$$
with the condition that $ n = 3k $ for some integer $ k $, and we are to **determine the order of $ x $** and **decide whether the order of $ x $ must be exactly 3** under this condition.
---
### Step 1: Understand the re... | 3 | true | 34,152 |
Evaluate the limit \( f(x) = \lim_{n \to \infty} \left(n \int_0^{\frac{\pi}{4}} (\tan x)^n \, dx\right) \) using appropriate mathematical techniques.
Please reason step by step, and put your final answer within \boxed{}. | We are asked to evaluate the limit:
$$
f(x) = \lim_{n \to \infty} \left(n \int_0^{\frac{\pi}{4}} (\tan x)^n \, dx\right)
$$
Note: The notation $ f(x) $ is misleading here since the expression does not depend on $ x $ — it's a limit of an integral involving $ n $. So we'll interpret this as evaluating:
$$
\lim_{n \to... | \dfrac{1}{2} | true | 30,806 |
Does there exist a degree 6 irreducible polynomial in \( \mathbb{Q}[x] \) whose Galois group is isomorphic to \( S_3 \), the symmetric group of degree 3?
Please reason step by step, and put your final answer within \boxed{}. | We are asked whether there exists a **degree 6 irreducible polynomial** in $ \mathbb{Q}[x] $ whose **Galois group is isomorphic to $ S_3 $**, the symmetric group on 3 letters.
Let’s analyze this step by step.
---
### Step 1: Understand the structure of $ S_3 $
- $ S_3 $ is the symmetric group on 3 elements.
- It ha... | Yes | true | 5,115 |
Let $C \subset \mathbb{R}^2$ be an algebraic curve defined by an irreducible polynomial $P$. Suppose $Q \in \mathbb{R}[x,y]$ is another polynomial such that $Q(x,y) = 0$ on a set $A \subset C$ where $A$ has a limit point. Does it follow that $P$ divides $Q$?
Please reason step by step, and put your final answer within ... | We are given the following:
- $ C \subset \mathbb{R}^2 $ is an algebraic curve defined by an irreducible polynomial $ P \in \mathbb{R}[x, y] $. So,
$$
C = \{(x, y) \in \mathbb{R}^2 \mid P(x, y) = 0\}.
$$
- $ Q \in \mathbb{R}[x, y] $ is another polynomial such that $ Q(x, y) = 0 $ on a set $ A \subset C $, and $ ... | Yes | true | 30,964 |
Find the smallest real number \( C \) such that the inequality \[ C(x_1^{2005} +x_2^{2005} + \cdots + x_5^{2005}) \geq x_1x_2x_3x_4x_5(x_1^{125} + x_2^{125}+ \cdots + x_5^{125})^{16} \] holds for all positive real numbers \( x_1, x_2, x_3, x_4, x_5 \).
Please reason step by step, and put your final answer within \boxed... | We are given the inequality:
$$
C(x_1^{2005} + x_2^{2005} + \cdots + x_5^{2005}) \geq x_1x_2x_3x_4x_5(x_1^{125} + x_2^{125} + \cdots + x_5^{125})^{16}
$$
for all positive real numbers $ x_1, x_2, x_3, x_4, x_5 $, and we are to find the **smallest** real number $ C $ such that this holds.
---
### Step 1: Understand ... | 5^{15} | true | 55,725 |
Evaluate the limit: \[ \lim_{n \to \infty} \frac{n \log_2( \log_2 n)}{3^{\log_2 n^2}}. \]
Please reason step by step, and put your final answer within \boxed{}. | We are asked to evaluate the limit:
$$
\lim_{n \to \infty} \frac{n \log_2( \log_2 n)}{3^{\log_2 n^2}}.
$$
Let’s simplify this expression step by step.
---
### Step 1: Simplify the exponent in the denominator
We have:
$$
3^{\log_2 n^2}
$$
First, simplify $\log_2 n^2$:
$$
\log_2 n^2 = 2 \log_2 n
$$
So the denomina... | 0 | true | 17,251 |
Evaluate the improper integral \( \int_{0}^{\infty}\frac{\sin^2t}{t^2}dt \) using Laplace transforms.
Please reason step by step, and put your final answer within \boxed{}. | We are asked to evaluate the improper integral
$$
\int_{0}^{\infty} \frac{\sin^2 t}{t^2} \, dt
$$
using **Laplace transforms**. Let's proceed step by step.
---
### Step 1: Use a known identity for $\sin^2 t$
Recall the trigonometric identity:
$$
\sin^2 t = \frac{1 - \cos(2t)}{2}
$$
So the integral becomes:
$$
\... | \dfrac{\pi}{2} | true | 38,857 |
Evaluate the contour integral \( \oint_{|z|=1} |z-1|^2 \, dz \), where \( z \) is a complex number and the integration is performed along the circle of radius 1 centered at the origin.
Please reason step by step, and put your final answer within \boxed{}. | We are asked to evaluate the contour integral:
$$
\oint_{|z|=1} |z - 1|^2 \, dz
$$
where the contour is the unit circle $ |z| = 1 $, traversed once counterclockwise.
---
### Step 1: Understand the integrand
The integrand is $ |z - 1|^2 $. Since $ z $ is a complex variable on the unit circle, we can write $ z = e^{... | -2\pi i | true | 29,084 |
Evaluate the contour integral \( \frac{1}{2\pi i} \oint_y \frac{f(C)}{(C-z)^2}dC \), where \( f: \mathbb{C} \to \mathbb{C} \) is holomorphic and \( y \) is a closed circle centered at \( z \in \mathbb{C} \), traced anticlockwise. Determine if the value of this integral is \( f'(z) \).
Please reason step by step, and pu... | We are asked to evaluate the contour integral:
$$
\frac{1}{2\pi i} \oint_\gamma \frac{f(C)}{(C - z)^2} \, dC
$$
where:
- $ f: \mathbb{C} \to \mathbb{C} $ is **holomorphic** (entire, in fact, since domain is all of $ \mathbb{C} $),
- $ \gamma $ is a **closed circle** centered at $ z \in \mathbb{C} $, traced **anticloc... | f'(z) | true | 15,262 |
Given a finite group $G$ and a subgroup $H$ of $G$, determine if there exist elements $x, y \in G \setminus H$ such that the number of left cosets of $H$ containing $x$ is different from the number of right cosets of $H$ containing $y$. Answer with "Yes" or "No".
Please reason step by step, and put your final answer wi... | We are given a finite group $ G $ and a subgroup $ H \leq G $. We are to determine whether there exist elements $ x, y \in G \setminus H $ such that:
> The number of **left cosets** of $ H $ containing $ x $ is different from the number of **right cosets** of $ H $ containing $ y $.
Let’s analyze this step by step.
... | No | true | 49,062 |
Given the function \( f(x) = e^{\frac{x^2}{2}} + \int_0^x tf(t)dt \), determine which of the following intervals contains \( f(\sqrt{2}) \):
A) \( 5 < f(\sqrt{2}) < 6 \)
B) \( 2 < f(\sqrt{2}) < 3 \)
C) \( 3 < f(\sqrt{2}) < 4 \)
D) \( 4 < f(\sqrt{2}) < 5 \)
Please reason step by step, and put your final answer wi... | We are given the function:
$$
f(x) = e^{\frac{x^2}{2}} + \int_0^x t f(t)\,dt
$$
We are to estimate $ f(\sqrt{2}) $ and determine which interval it lies in.
---
### Step 1: Understand the structure of $ f(x) $
The function is defined in terms of itself via an integral. This suggests we may need to differentiate $ f... | A | true | 48,613 |
A parabola has its focus at point $F$ and its vertex at point $V$, with $VF = 10$ units. A chord $AB$ of length $100$ units passes through $F$. Given the parabola equation $y^2 = 4ax$, determine the area of triangle $VAB$.
Please reason step by step, and put your final answer within \boxed{}. | We are given:
- A parabola with equation $ y^2 = 4ax $
- Focus at point $ F $
- Vertex at point $ V $
- Distance $ VF = 10 $ units
- A chord $ AB $ of length 100 units passes through the focus $ F $
- We are to find the **area of triangle $ VAB $**
---
### Step 1: Understand the standard parabola $ y^2 = 4ax $
For ... | 100\sqrt{10} | true | 22,395 |
Calculate the remainder when $73^{1567}$ is divided by 990 using the Chinese Remainder Theorem.
Please reason step by step, and put your final answer within \boxed{}. | We are asked to compute the **remainder when $ 73^{1567} $ is divided by 990**, i.e.,
$$
73^{1567} \mod 990
$$
We'll use the **Chinese Remainder Theorem (CRT)**. First, factor 990:
$$
990 = 2 \times 3^2 \times 5 \times 11
$$
So, we will compute $ 73^{1567} \mod 2 $, $ \mod 9 $, $ \mod 5 $, and $ \mod 11 $, then com... | 127 | true | 13,587 |
Given real numbers \(a_{1}, a_{2}, \ldots, a_{7}\) such that \(a_{1} = a_{7} = 0\), determine if there is always an index \(k \leq 5\) such that the inequality \(a_{k} + a_{k+2} \leq a_{k+1} \sqrt{3}\) holds.
Please reason step by step, and put your final answer within \boxed{}. | We are given real numbers $ a_1, a_2, \ldots, a_7 $ such that:
- $ a_1 = a_7 = 0 $
- We are to determine whether **there is always** an index $ k \leq 5 $ such that:
$$
a_k + a_{k+2} \leq a_{k+1} \sqrt{3}
$$
We are to decide whether **this inequality must hold for at least one** $ k = 1, 2, 3, 4, 5 $, **no matt... | Yes | true | 53,216 |
Determine the spectrum of the operator $T: C[0,1] \to C[0,1]$ defined by $Tf(x) = \int_0^x f(t) \, dt$.
Please reason step by step, and put your final answer within \boxed{}. | We are given a linear operator $ T: C[0,1] \to C[0,1] $ defined by
$$
Tf(x) = \int_0^x f(t)\,dt.
$$
Our goal is to **determine the spectrum** of $ T $, denoted $ \sigma(T) $, where $ T $ acts on the space $ C[0,1] $ of continuous real- (or complex-) valued functions on $[0,1]$, equipped with the **supremum norm**:
$... | \{0\} | true | 46,745 |
Two SFT trajectory datasets used in the OPSFT release.
deepmath/ — DeepMath trajectories generated with Qwen3-30B (train.parquet, validation.parquet)eurus/ — Eurus trajectories generated with Qwen3-30B-A3B (non-thinking) (train.parquet, validation.parquet)Parquet. Each row is one (prompt, trajectory) pair for supervised fine-tuning.
Research on supervised fine-tuning and distillation. Not for deployment.
Trajectory data is released under the Qwen License Agreement. Verify licensing of the underlying prompts/sources before redistribution.