几道初一有理数计算题.1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*212.1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/2008+2/2008+....+2007/2008)3.1又1/2+2又1/4+3又1/8+....+8又1/256 要过程!
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/13 06:44:28
![几道初一有理数计算题.1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*212.1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/2008+2/2008+....+2007/2008)3.1又1/2+2又1/4+3又1/8+....+8又1/256 要过程!](/uploads/image/z/444491-35-1.jpg?t=%E5%87%A0%E9%81%93%E5%88%9D%E4%B8%80%E6%9C%89%E7%90%86%E6%95%B0%E8%AE%A1%E7%AE%97%E9%A2%98.1.%EF%BC%881%2F3-7%2F12%2B9%2F20-11%2F30%2B13%2F42-15%2F56%EF%BC%89%2A8%2A212.1%2F2%2B%EF%BC%881%2F3%2B2%2F3%EF%BC%89%2B%EF%BC%881%2F4%2B2%2F4%2B3%2F4%EF%BC%89%2B...%2B%EF%BC%881%2F2008%2B2%2F2008%2B....%2B2007%2F2008%EF%BC%893.1%E5%8F%881%2F2%2B2%E5%8F%881%2F4%2B3%E5%8F%881%2F8%2B....%2B8%E5%8F%881%2F256+%E8%A6%81%E8%BF%87%E7%A8%8B%EF%BC%81)
几道初一有理数计算题.1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*212.1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/2008+2/2008+....+2007/2008)3.1又1/2+2又1/4+3又1/8+....+8又1/256 要过程!
几道初一有理数计算题.
1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*21
2.1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/2008+2/2008+....+2007/2008)
3.1又1/2+2又1/4+3又1/8+....+8又1/256
要过程!
几道初一有理数计算题.1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*212.1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/2008+2/2008+....+2007/2008)3.1又1/2+2又1/4+3又1/8+....+8又1/256 要过程!
1.(1/3-7/12+9/20-11/30+13/42-15/56)*8*21
=56-42+378/5-308/5+52-45
=14+70/5+7
=35
2.1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+...+(1/2008+2/2008+.+2007/2008)
=1/2+(1/3+2/3)+((1/4+3/4)+2/4)+((1/5+4/5)+(2/5+3/5))+...+((1/2008+2007/2008)+(2/2008+2006/2008)+.)
=1/2+(1)+(1+2/4)+(1+1)+...+(1+1+1...)
=(1/2)*2007+(2007*2006)*(1/2)/2
=2007/2+(2007*1003)/2
=(2007/2)*(1+1003)
=(2007/2)*1004
=2007*502
=1007514
3.1又1/2+2又1/4+3又1/8+.+8又1/256
=(1+2+3+...+8)又(1/2+1/4+1/8+...+1/256)
=36又((128+64+32+16+8+4+2+1)/256)
=36又(255/256)