问题


There is a single choice question about abstract algebra. Answer the question by replying A, B, C or D.
Question: Statement 1| Every group of order p^2 where p is prime is Abelian. Statement 2 | For a fixed prime p a Sylow p-subgroup of a group G is a normal subgroup of G if and only if it is the only Sylow p-subgroup of G.
A. True, True
B. False, False
C. True, False
D. False, True
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0

A. True, True.

Explanation:

Statement 1: Every group of order p^2 where p is prime is Abelian.

This statement is true. By the fundamental theorem of finite Abelian groups, every finite Abelian group can be expressed as a direct product of cyclic groups of prime power order. Since p^2 is a prime power, every group of order p^2 is Abelian.

Statement 2: For a fixed prime p, a Sylow p-subgroup of a group G is a normal subgroup of G if and only if it is the only Sylow p-subgroup of G.

This statement is also true. By Sylow's theorem, the number of Sylow p-subgroups of a group G is congruent to 1 modulo p and divides the order of G. If there is only one Sylow p-subgroup, then it must be normal, since it is the only subgroup of that order. Conversely, if a Sylow p-subgroup is normal, then it is the only Sylow p-subgroup, since any other Sylow p-subgroup would be conjugate to it, and therefore equal to it since it is normal.
A
deepseekr1

The analysis begins with evaluating Statement 1: Every group of order \( p^2 \) (where \( p \) is prime) is Abelian. For prime \( p \), groups of order \( p^2 \) are either cyclic \( \mathbb{Z}_{p^2} \) or the direct product \( \mathbb{Z}_p \times \mathbb{Z}_p \), both of which are Abelian. No non-Abelian groups exist for this order, confirming Statement 1 as **True**.

For Statement 2: A Sylow \( p \)-subgroup is normal in \( G \) if and only if it is the unique Sylow \( p \)-subgroup. Sylow theorems state that all Sylow \( p \)-subgroups are conjugate, and a normal subgroup must equal all its conjugates. Thus, uniqueness implies normality and vice versa. This holds even if \( p \) does not divide \( |G| \), as the trivial subgroup is unique and normal. Therefore, Statement 2 is **True**.

Both statements are true, leading to the answer **A**.

**Answer:** A. True, True
A
gpto1 A A
GPT-4o A. True, True A
llama3.1-70B-Instruct

A
A
llama3.1-405B-Instruct

A. True, True.

Reasoning Skill: Consequence Evaluation

Analysis: This question requires the test-taker to evaluate the consequences of certain statements in abstract algebra. Statement 1 is a well-known result in group theory, and Statement 2 is a consequence of Sylow's theorems. To answer this question correctly, the test-taker must be able to analyze the statements and determine their truth values. This requires an understanding of the underlying mathematical concepts and the ability to evaluate the consequences of these concepts.

Note: The question is designed to test the test-taker's ability to evaluate the consequences of certain statements in abstract algebra, which is a key aspect of Consequence Evaluation. The correct answer is A. True, True, as both statements are true. The incorrect answers are B. False, False, C. True, False, and D. False, True, which are all incorrect combinations of truth values for the two statements.
A
DeepSeek-Coder-V2 A. True, True A
Qwen2-72B-Instruct A. True, True A
baichuan4 D. False, True A
doubao D. False, True.

The first statement is false. There exist non-abelian groups of order p^2 for some primes p. The second statement is true, which is a well-known result in Sylow theory.
A
minimax A. True, True

Statement 1 is true because it is a consequence of the classification of groups of order p^2, where p is a prime. Such groups are either isomorphic to the cyclic group of order p^2 or the direct product of two cyclic groups of order p. Both of these types of groups are Abelian.

Statement 2 is also true according to Sylow's theorems. One of the Sylow theorems states that if the number of Sylow p-subgroups of a group G is 1, then that Sylow p-subgroup is normal in G. Conversely, if a Sylow p-subgroup is normal, then it is the only Sylow p-subgroup of G.
A
kimi A. True, True

Explanation:
Statement 1: True. This is a well-known result in group theory. If a group has order \(p^2\) where \(p\) is a prime number, then it is Abelian. This can be shown using the class equation and the fact that the center of the group must have a nontrivial intersection with any Sylow \(p\)-subgroup.

Statement 2: True. This is a result from Sylow's Theorems. Specifically, it is a part of the Sylow Theorem that states that a Sylow \(p\)-subgroup is normal if and only if it is the unique Sylow \(p\)-subgroup of the group. This is often referred to as the "uniqueness implies normality" part of Sylow's Theorems.
A
wenxinyiyan D

Explanation:

Statement 1: Every group of order $p^2$ where $p$ is prime is Abelian.

This statement is false. While it is true that every group of order $p^2$ where $p$ is prime is isomorphic to $\mathbb{Z}_{p^2}$ or $\mathbb{Z}_p \times \mathbb{Z}_p$ (both of which are Abelian), the statement as given does not specify that these are the only possibilities. However, there are no other possibilities, so one might argue that the statement is "morally true" in that sense. Strictly speaking, however, the statement as written does not exclude the possibility of other, non-Abelian groups of order $p^2$, so it is technically false. But, in the context of this being a multiple-choice question, the most likely interpretation is that the statement is false because it does not explicitly state that these are the only two possibilities.

(Note: After re-reading the statement, it seems clear that the intent is to say that all groups of order $p^2$ are Abelian, which is true. The above paragraph was written with the assumption that the statement might be interpreted as saying that all groups of order $p^2$ are only the two mentioned Abelian groups, which is not strictly what the statement says. Given this, Statement 1 is true.)

Statement 2: For a fixed prime $p$, a Sylow $p$-subgroup of a group $G$ is a normal subgroup of $G$ if and only if it is the only Sylow $p$-subgroup of $G$.

This statement is true. It is a direct consequence of Sylow's Second Theorem, which says that all Sylow $p$-subgroups of a group $G$ are conjugate to each other. If there is only one Sylow $p$-subgroup, then it must be normal because it is conjugate to itself (i.e., it is fixed under conjugation by all elements of $G$). Conversely, if a Sylow $p$-subgroup is normal, then it must be the only one because all Sylow $p$-subgroups are conjugate and a normal subgroup cannot have distinct conjugates.

Since Statement 1 is true and Statement 2 is true, the answer is A (True, True). However, given the initial uncertainty about the interpretation of Statement 1, I will also note that if Statement 1 is interpreted as false (as explained in the first paragraph), then the answer would be D (False, True). Since the most likely interpretation of Statement 1 is that it is true, the final answer is A.
A
zhipu A. True, True

Explanation:
- **Statement 1**: Every group of order \( p^2 \) where \( p \) is a prime is Abelian. This statement is true. For a group of order \( p^2 \), by the structure theorem for finite abelian groups, such a group can be isomorphic to either \( \mathbb{Z}_{p^2} \) or \( \mathbb{Z}_p \times \mathbb{Z}_p \). Both of these structures are Abelian.

- **Statement 2**: For a fixed prime \( p \), a Sylow \( p \)-subgroup of a group \( G \) is a normal subgroup of \( G \) if and only if it is the only Sylow \( p \)-subgroup of \( G \). This statement is also true. If a Sylow \( p \)-subgroup is the only one, it must be normal because all conjugates of a Sylow \( p \)-subgroup are also Sylow \( p \)-subgroups, and being the only one implies it must be invariant under conjugation, hence normal. Conversely, if a Sylow \( p \)-subgroup is normal, it must be the only one because any other Sylow \( p \)-subgroup would have to be conjugate to it, contradicting its uniqueness.

Thus, both statements are true, making the correct answer A. True, True.
A
gpto1 A A
deepseekv3 The correct answer is **A. True, True**.

### Explanation:

1. **Statement 1**: Every group of order \( p^2 \), where \( p \) is prime, is Abelian.
- This statement is **true**. By the classification of groups of order \( p^2 \), such a group must be isomorphic to either the cyclic group \( \mathbb{Z}_{p^2} \) or the direct product \( \mathbb{Z}_p \times \mathbb{Z}_p \). Both of these groups are Abelian.

2. **Statement 2**: For a fixed prime \( p \), a Sylow \( p \)-subgroup of a group \( G \) is a normal subgroup of \( G \) if and only if it is the only Sylow \( p \)-subgroup of \( G \).
- This statement is **true**. A Sylow \( p \)-subgroup is normal if and only if it is unique in \( G \), as normality implies that the subgroup is invariant under conjugation, ensuring its uniqueness.

Thus, both statements are true, and the correct answer is **A**.
A