Let p(x)= x3+(5m+1)x+5n+1, where m,n are integers. Which of the following statements is not true?( )
A: Q[x]/ is field.
B: p(x) is irreducible over Q[x]
C: x+ has multiplicative inverse in Q[x]/.
D: Q[x]/ is an integer domain but not a field
A: Q[x]/ is field.
B: p(x) is irreducible over Q[x]
C: x+ has multiplicative inverse in Q[x]/.
D: Q[x]/ is an integer domain but not a field
D
举一反三
- ( )不是有效的推理。 A: 前提:("x)(H(x)ÞM(x)) 结论:("x)("y)(H(y)∧N(x, y))Þ($y)(M(y)∧N(a, y)) B: 前提:("x)(G(x)ÞH(x)),~($x)(F(x)∧H(x)) 结论:($x)F(x)Þ($x)G(x) C: 前提:("x)(P(x)ÞQ) 结论:("x)P(x)ÞQ D: 前提:("x)P(x)∨("x)Q(x) 结论:("x)(P(x)∨Q(x))
- ( )不是有效的推理。 A: 前提:("x)(~P(x)ÞQ(x)), ("x)~Q(x)结论:P(a) B: 前提:("x)(P(x)ÞQ) 结论:("x)P(x)ÞQ C: 前提:("x)(P(x)∨Q(x)), ("x)(Q(x)Þ~R(x)) 结论:($x)(R(x)ÞP(x)) D: 前提:("x)(P(x)Þ(Q(x)∧R(x))), ($x)(P(x)∧S(x))结论:("x)(R(x)∧S(x)) E: 前提:("x)($y)P(x, y)结论:("x)($y)($z)(P(x, y)∧P(y, z)) F: 前提:("x)P(x)∨("x)Q(x)结论:("x)(P(x)∨Q(x)) G: 前提:("x)(G(x)ÞH(x)),~($x)(F(x)∧H(x))结论:($x)F(x)Þ($x)G(x) H: 前提:("x)(H(x)ÞM(x))结论:("x)("y)(H(y)∧N(x, y)) Þ ($y)(M(y)∧N(a, y) )
- 在指定的解释下,下列公式为真的是() A: ("x)(P(x)∨Q(x)),P(x):x=1,Q(x):x=2,论域:{1,2} B: ($x)(P(x)∧Q(x)),P(x):x=1,Q(x):x=2,论域: {1,2} C: ($x)(P(x) →Q(x)),P(x):x>2,Q(x):x=0,论域:{3,4} D: ("x)(P(x)→Q(x)),P(x):x>2,Q(x):x=0,论域:{3,4}
- 以下谓词公式中,( )不是逻辑有效式。 A: ($x)(P(x)∧Q(x)) Þ ($x) P(x)∧($x) Q(x) B: ("x)(P(x)∧Q(x)) Þ ("x) P(x)∧("x) Q(x) C: ($x)(P(x)∧Q(x)) Û ($x) P(x)∧($x) Q(x) D: ("x)(P(x)∧Q(x)) Û ("x) P(x)∧("x) Q(x)
- 以下谓词公式中,( )不是逻辑有效式。 A: ($x) P(x)∨($x) Q(x) Þ ($x)(P(x)∨Q(x)) B: ("x) P(x)∨("x) Q(x) Þ ("x)(P(x)∨Q(x)) C: ($x) P(x)∨($x) Q(x) Û ($x)(P(x)∨Q(x)) D: ("x) P(x)∨("x) Q(x) Û ("x)(P(x)∨Q(x))
内容
- 0
∀x(P(x)∧Q(x))的否定是? A: ∃x(P(x)∧Q(x)) B: ∃x(¬P(x)∨Q(x)) C: ∃x(¬P(x)∨¬Q(x)) D: ∃x(¬P(x)∧¬Q(x))
- 1
设有关键字序列F={Q,G,M,Z,A,N,P,X,H},下面( )序列是从上述序列出发建堆的结果。 A: A,G,H,M,N,P,Q,X,Z B: A,G,M,H,Q,N,P,X,Z C: G,M,Q,A,N,P,X,H,Z D: H,G,M,P,A,N,Q,X,Z
- 2
设有一个关键码序列:Q,G,M,Z,A,N,P,X,H;下列序列中与上述序列对应的堆是________。 A: A,G H,M,N,P,Q,X,Z B: A,G M,H,Q,N,P,X,Z C: G M,Q,A,N,P,X,H,Z D: H,G M,P,A,N,Q,X,Z
- 3
设有关键码序列(q,g,m,z,a,n,p,x,h),下面的序列()是从上述序列出发建堆的结果。 A: a,g,h,m,n,p,q,x,z B: a,g,m,h,q,n,p,x,z C: g,m,q,a,n,p,x,h,z D: h,g,m,p,a,n,q,x,z
- 4
前提:∀x(P(x)→Q(x)),∃xP(x) ⇒∃xQ(x) (1)∀x(P(x) → Q(x)) 前提 (2) ∃xP(x) 前提 (3) P(c) (2), Es规则 (4)P(c)→Q(c) (1), Us规则 (5) Q(c) (3)(4), 假言推理I (6)∃xQ(x) (5), Eg规则 上述推理过程是否正确?