问题


There is a single choice question about abstract algebra. Answer the question by replying A, B, C or D.
Question: Statement 1 | If a R is an integral domain, then R[x] is an integral domain. Statement 2 | If R is a ring and f(x) and g(x) are in R[x], then deg (f(x)g(x)) = deg f(x) + deg g(x).
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.

Reasoning Skill for Scientific Evidence Evaluation: This question requires the ability to analyze and evaluate the truth of mathematical statements, specifically in the context of abstract algebra. The correct answer, A. True, True, demonstrates an understanding of the properties of integral domains and polynomial rings. The incorrect answers, B. False, False, C. True, False, and D. False, True, represent common misconceptions or misunderstandings of these concepts. To answer this question correctly, one must be able to evaluate the evidence presented in the statements and apply their knowledge of abstract algebra to determine the truth of each statement. This requires critical thinking, analytical skills, and a strong foundation in mathematical concepts.

Note: This question is designed to test the ability to evaluate scientific evidence in the context of abstract algebra, which is a fundamental aspect of scientific evidence evaluation in mathematics. The correct answer demonstrates an understanding of the underlying mathematical concepts and the ability to apply them to evaluate the truth of the statements.
C
deepseekr1

The first statement is true because if \( R \) is an integral domain, the polynomial ring \( R[x] \) retains the property of having no zero divisors, ensuring it is also an integral domain. The second statement is false because the degree of a product of polynomials in \( R[x] \) equals the sum of their degrees only if \( R \) is an integral domain. In general rings (with zero divisors), this equality may fail.

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

A
C
llama3.1-405B-Instruct

A. True, True.
Explanation: If R is an integral domain, then R[x] is an integral domain. If R is a ring and f(x) and g(x) are in R[x], then deg (f(x)g(x)) = deg f(x) + deg g(x).
C
DeepSeek-Coder-V2 A C
Qwen2-72B-Instruct A. True, True C
baichuan4 A. True, True C
doubao C

The first statement is true. If R is an integral domain, then R[x] is also an integral domain.

The second statement is false. In general, deg (f(x)g(x)) is less than or equal to deg f(x) + deg g(x), not always equal.
C
minimax C. True, False

Explanation:
Statement 1 is true. If R is an integral domain, then R[x] is also an integral domain. This is because in an integral domain, there are no zero divisors, meaning that if ab = 0, then either a = 0 or b = 0. This property is preserved when we move to the polynomial ring R[x], as the product of two non-zero polynomials in R[x] cannot be the zero polynomial unless one of the polynomials is itself the zero polynomial.

Statement 2 is false. The degree of the product of two polynomials is equal to the sum of their degrees only if the leading coefficients of the polynomials are non-zero. If either f(x) or g(x) is the zero polynomial, then deg(f(x)g(x)) is not defined (since the zero polynomial does not have a degree). Additionally, if R is not a field, there is no guarantee that the leading coefficients will be units (invertible elements), and thus the degree of the product might not be the sum of the degrees. For example, if R is Z/6Z, and f(x) = 2x + 1 and g(x) = 3x + 2, then f(x)g(x) = (2x + 1)(3x + 2) = 6x^2 + 4x + 2, which is the zero polynomial in R[x] because 6 is a zero divisor in Z/6Z. In this case, deg(f(x)g(x)) is not equal to deg(f(x)) + deg(g(x)).
C
kimi C. True, False

Explanation:
Statement 1: If a R is an integral domain, then R[x] is an integral domain. This statement is true. An integral domain is a commutative ring with no zero divisors. If R is an integral domain, then the ring of polynomials R[x] over R is also an integral domain because the product of two non-zero polynomials in R[x] will not be zero.

Statement 2: If R is a ring and f(x) and g(x) are in R[x], then deg (f(x)g(x)) = deg f(x) + deg g(x). This statement is false. The degree of the product of two polynomials is the sum of their degrees only if the leading coefficients are non-zero. If either f(x) or g(x) has a leading coefficient of zero, then the degree of the product will be less than the sum of the degrees of f(x) and g(x).
C
wenxinyiyan B. False, False

Explanation:

1. Statement 1: If R is an integral domain, then R[x] is an integral domain.


* This statement is false. Consider the ring of polynomials with coefficients in the integers modulo 4, denoted by $(\mathbb{Z}/4\mathbb{Z})[x]$. The ring $\mathbb{Z}/4\mathbb{Z}$ is not an integral domain because $2 \times 2 = 0$ in this ring, but 2 is not zero. Hence, $(\mathbb{Z}/4\mathbb{Z})[x]$ is not an integral domain either, despite $\mathbb{Z}$ being an integral domain. This counterexample shows that R being an integral domain does not imply R[x] is an integral domain.
2. Statement 2: If R is a ring and f(x) and g(x) are in R[x], then $\deg (f(x)g(x)) = \deg f(x) + \deg g(x)$.


* This statement is also false. Consider the ring of polynomials with real coefficients, $\mathbb{R}[x]$. Let $f(x) = x^2 + 1$ and $g(x) = -x^2 + 1$. The degrees of f(x) and g(x) are both 2. However, their product is $f(x)g(x) = (x^2 + 1)(-x^2 + 1) = -x^4 + 1$, which has degree 4, not $\deg f(x) + \deg g(x) = 2 + 2 = 4$ in this case, but the statement suggests this should hold for all rings R and all polynomials f(x) and g(x). In general, the degree of the product can be less than the sum of the degrees if the leading coefficients multiply to zero (as in this example), so the statement is false.
C
zhipu The correct answer is C. True, False.

Explanation:
- Statement 1: "If \( R \) is an integral domain, then \( R[x] \) is an integral domain." This statement is true. An integral domain is a ring with no zero divisors. If \( R \) is an integral domain, then the polynomial ring \( R[x] \) is also an integral domain because the product of any two non-zero polynomials in \( R[x] \) will be a non-zero polynomial.

- Statement 2: "If \( R \) is a ring and \( f(x) \) and \( g(x) \) are in \( R[x] \), then \( \deg(f(x)g(x)) = \deg(f(x)) + \deg(g(x)) \)." This statement is false. The degree of the product of two polynomials \( f(x) \) and \( g(x) \) in \( R[x] \) is indeed \( \deg(f(x)) + \deg(g(x)) \), but this holds only when \( f(x) \) and \( g(x) \) are both non-zero polynomials. The statement does not specify that \( f(x) \) and \( g(x) \) are non-zero, and in the case where either \( f(x) \) or \( g(x) \) is the zero polynomial, the degree of their product would be \(-\infty\) (or undefined in some conventions), not the sum of their degrees.

Therefore, the correct choice is C. True, False.
C
gpto1 C C
deepseekv3 The correct answer is **C. True, False**.

### Explanation:
1. **Statement 1**
If \( R \) is an integral domain, then \( R[x] \) is also an integral domain. This is true because the product of two nonzero polynomials in \( R[x] \) will have a leading term that is the product of the leading terms of the two polynomials. Since \( R \) is an integral domain, this product is nonzero, ensuring that \( R[x] \) is an integral domain.

2. **Statement 2**
If \( R \) is a ring and \( f(x) \) and \( g(x) \) are in \( R[x] \), then \( \deg(f(x)g(x)) = \deg f(x) + \deg g(x) \). This is not always true. It holds only if \( R \) is an integral domain. If \( R \) has zero divisors, the product of the leading coefficients of \( f(x) \) and \( g(x) \) could be zero, leading to \( \deg(f(x)g(x)) < \deg f(x) + \deg g(x) \).

Thus, Statement 1 is true, and Statement 2 is false.
**Answer: C. True, False**
C