2．试证明?(A??B)?(?B?C)??C??A
证明：?(A??B)?(?B?C)??C
?(?A?B)?(?B?C)??C
?(?A?B)?(?B??C)?(C??C) ?(?A?B)?((?B??C)???0) ?(?A?B)?(?B??C)
?(?A? (?B??C))?(B?(?B??C)) ?(?A? (?B??C))?0 ??A? (?B??C) ??(A?B?C)
故由左边不可推出右边?A
电大离散数学形考任务1答案
2．试证明?(A??B)?(?B?C)??C??A证明：?(A??B)?(?B?C)??C?(?A?B)?(?B?C)??C?(?A?B)?(?B??C)?(C??C)?(?A?B)?((?B??C)???0)?(?A?B)?(?B??C)?(?A?(?B??C))?(B?(?B??C))?(?A?(
推荐度：
点击下载文档文档为doc格式
