11/4/(2/3-(1/2+3/5)x5/9)怎么算
1x5+2x5+3x5+4x5+5x5… 麻烦给我一个公式.
11/4/(2/3-(1/2+3/5)x5/9)怎么算
sn=(2-3x5^-1)+(4-3x5^-2)+…+(2n-3x5^-n)要详解答案,急用!
必修五数列综合练习:求和:(2-3x5^-1)+(4-3x5^-2)+…+(2n-3x5^-n) 急用!
[(2/3-1/4)÷5/6+4/5]X5/11
解方程组X2+X3+X4=1 X1+X2+X3=5 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2
(1+2+3+4+5+6+7+8+9+10+11+12+13+14+15)x5=?
4x5-3x等于5怎么解
求前n项和1.1/(2X5),1/(5X8),1/(8X11)...2.2^2/(1X3),4^2/(3X5),6^2/
已知数据X1,X2,X3,X4,X5的平均数是X拔,则一组新数据X1+1,X2+2,X3+3,X4+4,X5+5的平均数
2/1x3+2/3X5+2/5x7=2/7x9+2/9x11
1/1x2+1/2x3+1/3x4+1/4x5.1/9x10简算