设[tex=2.786x1.0]FGVYxRqIWsnQ2nynAdkLQA==[/tex]为三事件,且[tex=24.357x1.357]GIL3ik71c/sU2lOXR94clEWhNyuUkbFEYnmH7LODamomrJ08HbaviLf8N1KlAfyEAZQtpRkBle+l2C+phu7T7Mmrqe+gJRZKsRUa4+KuQHU=[/tex]求[tex=2.786x1.0]ZN6rDAH7qXXvzCB4/63dKg==[/tex]至少有一个发生的概率.

求下列系统的零输入响应 [tex=2.286x1.357]Q9uGIQvru+tRYnSpePeBvw==[/tex], 已知激励 f(n) 在 n =0 时接入。  [tex=24.357x1.357]n5UTvGlYvQI9eWmU17kqtZtOyNJmKA0nDEBJaeTBDXNsBu+Sqr6FfUJyr0x/xMIdv7R8b2kNEw7hxhJZ8+W4HQ==[/tex][br][/br]

下列变量组（）是一个闭回路。 A: {x，x，x，x，x，x} B: {x，x，x，x，x} C: {x，x，x，x，x，x} D: {x，x，x，x，x，x}

以下谓词蕴含式正确的是（）: (∀x) (A(x)→B(x))=>( ∀x)A(x)→(∀x)B(x)|(∀x) (A(x)↔B(x))=>( ∀x)A(x)↔(∀x)B(x)|(∀x)A(x)∨(∀x)B(x)=>( ∀x) (A(x)∨B(x))|(∃x) (A(x)∧B(x))=>(∃x)A(x)∧(∃x)B(x)

以下谓词蕴含式正确的是（）: (?x) (A(x)→B(x))=>( ?x)A(x)→(?x)B(x)|(?x) (A(x)?B(x))=>( ?x)A(x)?(?x)B(x)|(?x)A(x)∨(?x)B(x)=>( ?x) (A(x)∨B(x))|(?x) (A(x)∧B(x))=>(?x)A(x)∧(?x)B(x)

下列式中错误的是： A: (∀x)(A(x)Úp(x)) Û (∀x)A(x)Ú (∀x)p(x) B: ($x)A(x) Ù p Û ($x)(A(x) Ù p ) C: (∀x)(A(x)ÚB(x)) Þ (∀x)A(x)Ú( ∀x)B(x) D: ($x)(A(x)ÙB(x)) Þ ($x)A(x)Ù( $x)B(x)

下列哪项属于肾功能不全的衰竭期（   ） 未知类型：{'options': ['[tex=23.857x1.357]84XcHeDxTZJno3BVgyvGO8AJvtCztiedN2HJqp2hA3779vCTLwckLVzll5iFcdKmKgLGaTsSdAugu4r7ucdqCH/Wtbz1OKuozRvodEgDAtP/SHaFX0yL0qlCEcmhvAwpS+/66eOHiFkMT6Tp4OP7IGMQH/65dhs8cZvlff6KAYvusTEvI1c7fb/bfMxGQ/cv[/tex]', '[tex=25.0x1.357]oU+F/zzYPksjZF/k2XWESycnEtuCqdmz5Ff+kOIxMIsDSwsPr2H+V1/PCJhssOmUl2/i8G0+vuPRkz3u8hEY3iy6Bpl5HK8VnCO/vdX1Ow6M4BI2EnGgnYjvQdOem6cVqDaEc/QsCt+f/wbpu1JkzicMO02N0Z334zX8wziUncs7cypqRF05lXfIRhNIsO5V[/tex]', '[tex=25.357x1.357]gYWLhrL9rueDE0QI03ICLxVtowOLKtvngOyHPvOerNTgT9nsxNeK7mveUKeqQRthmvqVxfVDW49RpQoBye9oNh0pT5YOpWQIQ6GlGu1P6dTluKInb7kodiYLWJqse3/SJ5IgEpTfwAz/wYpOkuA7eQ5zoUj7ZPuchWSDF6vcm5c=[/tex]', '[tex=24.857x1.357]XoFH4zYL4FWwm2npyyKB6KMTdcJe1YEwuAlDmagbsVXaDGuAXhM9JcnukhuEADeh4UENVgJGdZ7tv/iS0OerLA/e577IDzjYU540UOfR4pKtJhIfky6IA9DQd0/dyq0yA1rDKgFexIQJeFz9H9n7sgK+xAEiyzgFg1Vpu7VClT6csOWqg+46Z72+ecEFobH2[/tex]', '[tex=24.357x1.357]gYWLhrL9rueDE0QI03ICLxVtowOLKtvngOyHPvOerNTgT9nsxNeK7mveUKeqQRthq9NflGxfe24wnZaCVXDrATcjDl8zVcazTVyyOeJn7kmRc6HN7RMOAadj6Bh3nwExPHJAMGoTdFn68JSO7W27oeQevwWBc+rG6H0+MktsfQ8tvAtfnNnp9tZRvRsjifQF[/tex]'], 'type': 102}

判断下列推证是否正确。 (∀x)(A(x)→B(x))⇔(∀x)(￢A(x)∨B(x)) ⇔(∀x)￢( A(x)∧￢B(x) ) ⇔￢(∃x) ( A(x)∧￢B(x) ) ⇔￢( (∃x)A(x)∧(∃x)￢B(x) ) ⇔￢(∃x)A(x)∨￢(∃x)￢B(x) ⇔￢(∃x)A(x)∨(∀x)B(x) ⇔(∃x)A(x)→(∀x)B(x)

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))