the number of different prime factors of 48.和the number of different prime factors of 72

问题描述:

the number of different prime factors of 48.和the number of different prime factors of 72

48=(2*3)*(2*2*2)
so the number of different prime factors of 48 is 2 (only 2 and 3)
72=2*2*2*3*3
There are also two different prime factors of 72.
Hope this helps.