与公式("x)(P(x)∧Q(x, y))Þ($x)R(x, y)等值的是( )。选项: A:("x)(P(x)∧Q(x, z))Þ($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 等值 发布时间:2024-03-31 19:16:18