A=1/3+1/9+1/27+1/81+......+1/95049
Ax3=3x(1/3+1/9+1/27+1/81+.........+1/95049)
Ax3=1+1/3+1/9+1/27+1/81+..........+1/19683
Ax3-A=1+1/3+1/9+1/27+1/81+............+1/19683
- (1+1/3+1/9+1/27+1/81+........+1/59049)
=1-1/59049
2xA=59048/59049
A=59048/59049:2
A=29524/59049
mình ko biết làm
tính nhanh : A = 1/3 + 1/9 + 1/27 + 1/81+.....+1/59049
tính nhanh 1+3+9+27+81+243+729+2187+6561+19683+59049
tính nhanh
\(\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+....\frac{1}{59049}\)
Tính nhanh phân số :
1) 1/5+1/10+1/20+1/40+...........+1/1280.
2) 1/3+1/9+1/27+1/81+............+1/59049.
Trình bày giúp mình nha . Ai nhanh mk tick.
Tính nhanh
a, 1/5 + 1/10 + 1/20 + 1/40 + ... + 1/1280
b, 1/3 + 1/9 + 1/27 + 1/81 + ... +1/ 59049
Tính nhanh:
8-\(\frac{1}{3}\)+\(\frac{1}{9}\)+\(\frac{1}{27}\)+\(\frac{1}{81}\)+............+\(\frac{1}{59049}\)
\(\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+....+\frac{1}{59049}\)
tính nhanh :Bài 1: 1/3+1/9+1/27+1/81+1/243+1/729
Bài 2 : 1+5/4+5/8+5/16+5/32+5/64
Bài 3: 3/2+3/8+3/32+3/128+3/512
Bài 4: 3+3/5+3/25+3/125+3/625
Bài 5: 1/5+1/10+1/20+1/40+.........+1/1280
Bài 6: 1/3+1/9+1/27+1/81+.............+1/59049
Mk mong các bn giúp đỡ hãy lm đúng cho mk nha~mk cần rất gấp sáng mai rùi nha~
Bài 1:
\(a,\dfrac{1}{5}+\dfrac{1}{10}+\dfrac{1}{20}+\dfrac{1}{40}+...............+\dfrac{1}{1280}\)
\(b,\dfrac{1}{3}+\dfrac{1}{9}+\dfrac{1}{27}+\dfrac{1}{81}+..............+\dfrac{1}{59049}\)
\(c,\dfrac{1}{2}\times3+\dfrac{1}{3}\times4+\dfrac{1}{4}\times5+\dfrac{1}{5}\times6\)
