62、Do integers P and T have the same number of different prime factors?
(1)P=5/7T
(2)PT=35
【答案】C
【思路】
系数归一原则:当不存在常数项时,只要系数互质,你是我的倍数,我是你的倍数。根据这一原则:(1)P=5/7T—〉7P=5T,我们可以知道P是5的倍数,T是7的倍数。但是这并不能保证P和T有着相同的prime factors。但是如果结合(2)则只有一种情况就是:P为5,T为7,所以答案为C.
How about just B. Since P and T are integers, so only 5x7=35. And 5 and 7 have the same number of prrime factors?
am I missing somthing? 请指教 |