xdf数学请教

深海的小美人鱼

25. How many integers n are there such that
r < n < s?
(1) s – r = 5
(2) r and s are not integers.

Snazzy

B
1--> n= 4 or 5
2--> n=5

深海的小美人鱼

答案是C。郁闷。

我觉得A就可以满足了。小数也是一样的，因为N是整数

Snazzy

sorry, it's C
1--> n= 4(when r and s both are integers) or 5(when r and s both are not integers)
2--> nothing
1+2 -->n=5

深海的小美人鱼

多谢