问题


There is a single choice question about abstract algebra. Answer the question by replying A, B, C or D.
Question: Find the degree for the given field extension Q(sqrt(2)) over Q.
A. 0
B. 2
C. 1
D. 3
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0 B. 2 B
deepseekr1

The degree of a field extension \( \mathbb{Q}(\sqrt{2}) \) over \( \mathbb{Q} \) is determined by the dimension of \( \mathbb{Q}(\sqrt{2}) \) as a vector space over \( \mathbb{Q} \). Since \( \sqrt{2} \) is a root of the irreducible polynomial \( x^2 - 2 \) over \( \mathbb{Q} \), its minimal polynomial has degree 2. This implies \( \mathbb{Q}(\sqrt{2}) \) has a basis \( \{1, \sqrt{2}\} \), giving the extension degree 2.

Answer: B
B
gpto1 B B
GPT-4o B. 2 B
llama3.1-70B-Instruct

B
B
llama3.1-405B-Instruct B B
DeepSeek-Coder-V2 B B
Qwen2-72B-Instruct B. 2 B
baichuan4 B. 2 B
doubao B. 2. The degree of a field extension is determined by the degree of the minimal polynomial. The minimal polynomial of √2 over Q is x^2 - 2, which has degree 2. B
minimax B. 2 B
kimi B. 2 B
wenxinyiyan B. 2

Explanation:
The degree of a field extension K over F, denoted [K:F], is the dimension of K as a vector space over F. In this case, we have the field extension Q(sqrt(2)) over Q.

We can view Q(sqrt(2)) as a vector space over Q with basis {1, sqrt(2)}. This means that every element of Q(sqrt(2)) can be written as a linear combination of 1 and sqrt(2) with coefficients in Q.

For example, an element of Q(sqrt(2)) such as 3 + 4*sqrt(2) can be expressed as a linear combination of 1 and sqrt(2) as follows:

3 + 4*sqrt(2) = 3*1 + 4*sqrt(2)

Since the basis has 2 elements, the dimension of Q(sqrt(2)) as a vector space over Q is 2. Therefore, the degree of the field extension Q(sqrt(2)) over Q is 2.
B
zhipu B

The degree of the field extension \(\mathbb{Q}(\sqrt{2})\) over \(\mathbb{Q}\) is 2. This is because \(\sqrt{2}\) is a root of the polynomial \(x^2 - 2\), which is irreducible over \(\mathbb{Q}\). Therefore, \(\mathbb{Q}(\sqrt{2})\) is a degree 2 extension of \(\mathbb{Q}\).
B
gpto1 B B
deepseekv3 The degree of a field extension \( \mathbb{Q}(\sqrt{2}) \) over \( \mathbb{Q} \) is the dimension of \( \mathbb{Q}(\sqrt{2}) \) as a vector space over \( \mathbb{Q} \).

The minimal polynomial of \( \sqrt{2} \) over \( \mathbb{Q} \) is \( x^2 - 2 \), which has degree 2. Therefore, the degree of the extension \( \mathbb{Q}(\sqrt{2}) \) over \( \mathbb{Q} \) is 2.

Thus, the correct answer is:

**B. 2**
B