1/3+1/5+1/7+1/9+1/11+1/33+1/35+1/45+1/55+1/77=?
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/11 23:14:43
1/3+1/5+1/7+1/9+1/11+1/33+1/35+1/45+1/55+1/77=?
1/3+1/5+1/7+1/9+1/11+1/33+1/35+1/45+1/55+1/77
=1/3+1/5+1/7+1/9+1/11+(1/3-1/11)/8+(1/5-1/7)/2
+(1/5-1/9)/4+(1/5-1/11)/6+(1/7-1/11)/4
=1/3+1/5+1/7+1/9+1/11+(1/3)/8-(1/11)/8+(1/5)/2-(1/7)/2+
(1/5)/4-(1/9)/4+(1/5)/6-(1/11)/6+(1/7)/4-(1/11)/4
=(1/3)*[1+1/8]
+(1/5)*[1+1/2+1/4+1/6]
+(1/7)*[1-1/2+1/4]
+(1/11)*[1-1/8-1/6-1/4]
+(1/9)*[1-1/4]
=(1/3)*(9/8)+(1/5)*(23/12)+(1/7)*(3/4)+(1/11)*(11/24)+(1/9)*(3/4)
=(1/3)*(9/8)+(1/5)*(23/12)+(1/7)*(3/4)+1/24+1/12
=(3/8)+(1/5)*(23/12)+(1/7)*(3/4)+1/8
=1/2+(1/5)*(23/12)+(1/7)*(3/4)
=(6*5*7+23*7+3*3*5)/(12*5*7)
=[210+161+45]/(12*5*7)
=416/(12*5*7)
=104/105
简算:1/1*3+1/3*5+1/5*7+1/7*9+1/9*11
(1*3)/1+(3*5)/1+(5*7)/1+(7*9)/1+(9*11)/1
1/1*3+1/3*5+1/5*7+1/7*9+1/9*11
(1*3)/1+(3*5)/1+(5*7)/1+(7*9)/1+(9*11)/1
计算:1/3*5+1/5*7+1/7*9+1/9*11+1/11*13
1×3/1+3×5/1+5×7/1+7×9/1+9×11/1+11×13/1简便运算
计算:2/3*5+1/5*7+1/7*9+1/9*11+1/11*13
1/3+1/5+1/7+1/9+1/11+1/13+1/15=
1/3+1/5+1/7+1/9+1/11+1/13+...+1/99=?
1/1*3*5+1/3*5*7+1/5*7*9+1/7*9*11+1/9*11*13+1/11*13*15怎么计算
1/(1*3*5)+1/(3*5*7)+1/(5*7*9)+1/(7*9*11)+1/(9*11*13)+1/(11*13*15)等于多少
5 7 -5 3 9 -1 11 -3 1
1+3+5+7+9+11+.+99
1-3+5-7+9-11+13
1-3+5-7+9-11+.求救
1+3+5+7+9+11=?
1,3,5,7,9,11,15
计算:1-3 5-7 9-11