以下哪几项是前束范式？
A: (∀x)(∀y)(P(x)∧(∃z)Q(y,z)∨R(x,z))
B: (∀z)(∀x)(∃y)(P(x)∧Q(y,z)∨R(x,z))
C: (∀x)(∀y)(P(x)∧Q(y,z)∨(∃z)R(x,z))
D: (∃x)(∃y)(∀z)(P(x)∧Q(y,z)∨R(x,z))
A: (∀x)(∀y)(P(x)∧(∃z)Q(y,z)∨R(x,z))
B: (∀z)(∀x)(∃y)(P(x)∧Q(y,z)∨R(x,z))
C: (∀x)(∀y)(P(x)∧Q(y,z)∨(∃z)R(x,z))
D: (∃x)(∃y)(∀z)(P(x)∧Q(y,z)∨R(x,z))
举一反三
- 将公式∀x(P(x)→Q(x，y))∧R(x，y)使用改名规则变换后正确的是 。 A: ∀z(P(z)→Q(z，y))∧R(x，y) B: ∀y(P(y)→Q(y，y))∧R(x，y) C: ∀z(P(z)→Q(x，y))∧R(x，y) D: ∀z(P(z)→Q(z，y))∧R(z，y)
- 谓词公式∀xP(x)→∀xQ(x)∨∃yR(y)的前束范式为 A: ∀x∀z∃y(P(x)→Q(z) ∨ R( y)) B: ∃x∀z∃y(P(x)→Q(z) ∨ R( y)) C: ∀x∃y(P(x)→Q(x) ∨ R( y)) D: ∃x∀y(P(x)→Q(x) ∨ R( y))
- 与公式("x)(P(x)∧Q(x, y))Þ($x)R(x, y)等值的是（ ）。 A: ("x)(P(x)∧Q(x, z))Þ($x)R(x, y) B: ("y)(P(y)∧Q(y, y))Þ($x)R(x, y) C: ("z)(P(z)∧Q(x, y))Þ($x)R(x, y) D: ("u)(P(u)∧Q(u, z))Þ($x)R(x, z)
- 【单选题】与公式("x)(P(x)∧Q(x, y))Þ($x)R(x, y)等值的是()。 A. ( " x )( P ( x ) ∧ Q ( x , z )) Þ ( $ x ) R ( x , y ) B. ( " y )( P ( y ) ∧ Q ( y , y )) Þ ( $ x ) R ( x , y ) C. ( " z )( P (z ) ∧ Q ( x , y )) Þ ( $ x ) R ( x , y ) D. ( " u )( P ( u ) ∧ Q ( u , z )) Þ ( $ x ) R ( x , z )
- 公式$x(Ø$yP(x,y)®($zQ(z)®R(x)))的前束范式为$x$y$z(P(x,y)ÚØQ(z)ÚR(x)) A: 正确 B: 错误