Tính nhanh: A=1/3 - 3/4 - (-3/5)+1/72 - 2/9 - 1/36 - 1/15
Giải thích
A=13−34−−35+172−29−136+115=13−34+35+172−29−136+115=13+35+115+−34−29−136+172=515+915+115+−2736−836−136+172=1−1+172=172
A=13−34−−35+172−29−136+115=13−34+35+172−29−136+115=13+35+115+−34−29−136+172=515+915+115+−2736−836−136+172=1−1+172=172