2-1+3-2+4-3+……+50-49+51-50
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/08 09:25:28
![2-1+3-2+4-3+……+50-49+51-50](/uploads/image/z/241081-25-1.jpg?t=2-1%2B3-2%2B4-3%2B%E2%80%A6%E2%80%A6%2B50-49%2B51-50)
x)356565~M
tM,M
uM
l )/9 %@E@ez`y BP(eht\R\gu
dǒ';VȆ[45 t
31S
2-1+3-2+4-3+……+50-49+51-50
2-1+3-2+4-3+……+50-49+51-50
2-1+3-2+4-3+……+50-49+51-50
2-1+3-2+4-3+……+50-49+51-50
=(2-1)+(3-2)+.+(50-49)+(51-50)
=1+1+.+1
=1*50
=50
两个两个一组有50个-1