利用谓词的约束变元的换名规则和自由变元的代入规则，可将公式改写成______．
A: (x)(P(y)→Q(x，y))∧R(z，s)
B: (z)(P(z)→Q(z，s))∧R(x，s)
C: (x)(P(s)→Q(x，s))∧R(x，s)
D: (z)(P(s)→Q(z，s))∧R(z，s)
A: (x)(P(y)→Q(x，y))∧R(z，s)
B: (z)(P(z)→Q(z，s))∧R(x，s)
C: (x)(P(s)→Q(x，s))∧R(x，s)
D: (z)(P(s)→Q(z，s))∧R(z，s)
举一反三
- 谓词公式(x)(P(x)→Q(x,y)(z)R(y,z)) →S(x)中变元x 。6189ddf3bf26aeeaaf3d4b222c5678c7.gifcc54e24c7778432992553c244851cb68.gif32d769f8fd8371da08be7985dd5e3440.gif
- 公式("x) ($y)(P(x，z)→Q(y))→S(x，y)中的约束变元进行换名，正确的是 A: ("x) ($y) (P(x，u)→Q(y))→S(x，y) B: ("x) ($v)(P(u，z)→Q(v))→S(u，v) C: ("u) ($v) (P(u，z)→Q(v))→S(x，y) D: ("u) ($v)(P(u，t)→Q(v))→S(u，v)
- 对公式∀x∀y(P(x,y)∨Q(x,z))∧∃xP(x,y)使用代入和换名规则后得到的公式为( )。 A: ∀u∀y(P(u,y)∨Q(u,z))∧∃wP(w,s) B: ∀x∀u(P(x,u)∨Q(x,z))∧∃xP(x,y) C: ∀x∀y(P(x,y)∨Q(x,u))∧∃xP(x,s) D: ∀x∀y(P(x,y)∨Q(x,z))∧∃uP(u,z)
- 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)
- 在谓词公式(x)(P(x,y)→Q(x,z))∨(x)R(x,z)中y是自由变元