l******o 发帖数: 1550 | 1 for a sequence , x_(m,n)
is it true that
lim_m ( lim_n ) (x) = lim_n ( lim_m ) (x) (if exist, or even bounded)
iff lim_m (x),lim_n (x) exist for any n and m? | H****h 发帖数: 1037 | 2 未必。比如x_{m,n}=1 if m>n; =0 if n
【在 l******o 的大作中提到】 : for a sequence , x_(m,n) : is it true that : lim_m ( lim_n ) (x) = lim_n ( lim_m ) (x) (if exist, or even bounded) : iff lim_m (x),lim_n (x) exist for any n and m?
| l******o 发帖数: 1550 | 3 那有什么充要条件么?
【在 H****h 的大作中提到】 : 未必。比如x_{m,n}=1 if m>n; =0 if n
|
|