袋子中放有大小和形状相同的小球若干,其中标号为0的小球1个,标号为1的小球1个,标号为2的小球 n 个,已知从袋子中随机抽取1个小球,取到标号为2的小球的概率是 . (1)求 n 的值; (2)从袋子中不放回地随机抽取2个球,记第一次取出小球标号为 a ,第二次取出的小球标号为 b .①记“ a + b =2”为事件 A ,求事件 A 的概率; ②在区间[0,2]内2个实数 x , y ,求事件“ x 2 + y 2 >( a - b ) 2 恒成立”的概率.
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【简答题】I don’t think he can operate the new type of computer.英译汉
【单选题】A computer can think logically and work millions and millions of times faster than a human but it _____ never replace humans because it has to ________ to work. [ ]
【单选题】Can a computer think? That depends on what you mean by 'think'. If solving a mathematical problem is 'thinking', then a computer can 'think' and do so much faster than a man. Most mathematical problem...
A.
They are simple and they operate mechanically.
B.
They can solve all kinds of difficult problems.
C.
Computers are so advanced that they will control human being someday in the future.