Question

cho a =1/2+1/6+1/12+1/20+1/30+.....+1/n biet a +39/40

Answer 1

bài này có phải lớp 5 ko vậy tui thấy ? quá

Answer 2

IIIIIIIIIII       LLLLLLLLLL          oooooooooooo       vvvvvvvvvvvvvvvvvvv                 EEEEEEEEEEEEEEE

YYYYYYYYYYYYYYYYY               OOOOOOOOOOOOOOO                   UUUUUUUUUUUUUUU

I love you

k nha

hjhjhj

hahaha

hjhjhj

hahaha