1/3+1/9+/1/27+...+1/3^7=?
1/3+1/9+/1/27+...+1/3^7=?
Log3(9^2*27^(1/3))=?
1-1/3-1/9-1/27-1/81-1/243-1/729=?
1=0+12+3+4=1+85+6+7+8+9=8+27
(1/3+1/5)×15=?(1/9+1/3)×27=?(1/6+1/4)×36=?89×7/88=?要简便运算,
找规律1,5,3,7,9,9,27,( ),( )
1,5,3,7,9,9,27找规律
1/1*3+1/3*5+1/5*7+1/7*9+...1/17*19=
(1/3+1/5+1/7)*(1/5+1/7+1/9)-(1/3+1/5+1/7+1/9)*(1/5+1/7)=?
解方程:X*1/3*4/9=1/27
(1)3,9,27,81,243,729 ..(2) 1,7,25,79,241,727..(3) 1,3,9,27,8
1/3+1/9+1/27+1/81+1/243=?(要简便计算)