(1/2-1/4+1/6-1/8+1/10-1/12+……+1/198-1/200)÷(1/51+1/52+1/53+1
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/07/14 08:10:34
(1/2-1/4+1/6-1/8+1/10-1/12+……+1/198-1/200)÷(1/51+1/52+1/53+1/54+……1/100)
1/2-1/4+1/6-1/8+1/10-1/12+…+1/198-1/200
=(1-1/2+1/3-1/4+ ...+1/99-1/100)/2
=[(1+1/2+ ...+1/99+1/100)-2(1/2+1/4+ ...+1/98+1/100)]/2
=[(1+1/2+ ...+1/99+1/100)-(1+1/2+ ...+1/49+1/50)]/2
=(1/51+1/52+1/53+ ...+1/99+1/100)/2
所以原式
=(1/2)(1/51+1/52+1/53+ ...+1/99+1/100)/(1/51+1/52+1/53+…+1/100)
=1/2
=(1-1/2+1/3-1/4+ ...+1/99-1/100)/2
=[(1+1/2+ ...+1/99+1/100)-2(1/2+1/4+ ...+1/98+1/100)]/2
=[(1+1/2+ ...+1/99+1/100)-(1+1/2+ ...+1/49+1/50)]/2
=(1/51+1/52+1/53+ ...+1/99+1/100)/2
所以原式
=(1/2)(1/51+1/52+1/53+ ...+1/99+1/100)/(1/51+1/52+1/53+…+1/100)
=1/2
(1/2-1/4+1/6-1/8+1/10-1/12+……+1/198-1/200)÷(1/51+1/52+1/53+1
计算:(1/2-1/4+1/6-1/8+.+1/198-1/200)/(1/51+1/52+1/53+.+1/100)
(1/2—1/4+1/6—1/8+1/10+……+1/198—1/200)/1/51+1/52+……1/100=?
1-1/2+1/3-1/4+1/5-1/6…+1/99-1/100)/(1/51+1/52+1/53+…+1/99+1/
1/2+1/3-1/4×1/5÷1/6 + 1/7-1/8×1/9÷1/10………÷1/100=?
1/2*4+1/4*6+1/6*8+……+1/198*200
请问[1/(2+4)]+[1/(4+6)]+[1/(6+8)]+…+[1/(198+200)]=?
机算-1+2+3-4-5+6+7-8-9+10+11-12-……-2005+2006+2007-2008-2009的值?
【1/(1*2)+1/(3*4)+1/(5*6)+1/(7*8)+……1/(99*100)】/(1/51+1/52+……
1/2*4+1/4*6+1/6*8+1/8*10+---+1/198*200
求 :(1-1/2²)(1-1/3²)(1-1/4²)…(1-1/10²)…(1
1/1×3+1/3×5+1/5×7+…………+1/49×51和1/2×4+1/4×6+1/6×8+…………1/48×50