C= 2181 x 279 + 243 x 81 x 27
D= 9 x 81 x 243 + 18x 243 x324 + 723 x 729
tính C : D
Tính nhanh: 3+9+27+81+243+729
1/3+1/9+1/27+1/81+1/243+1/729
Tính nhanh phân số:
C= 2/3+2/8+2/27+2/81+2/243+2/729
1/3 + 1/9 + 1/27+1/81 + 1/243+ 1/729.
1/3+1/9+1/27+1/81+1/243+1/729 =?
1/3+1/9+1/27+1/81+1/243+1/729
tính nhanh 1+3+9+27+81+243+729+2187+6561+19683+59049
1/3 +1/9 + 1/27 + 1/81 + 1/243 + 1/729 + 1/2187 =?