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存档于 五月, 2010

Prove that square root of three is an irrational number.

via The Irrationality of Problem: Prove that is an irrational number. Solution: The number, , is irrational, ie., it cannot be expressed as a ratio of integers a and b. To prove that this statement is t...

Coins, dice, probability

1)Three dice are thrown simultaneously. The probability of obtaining a sum of 6 is? 1)1/24         2)5/108        3)1/54   ...