数学!高手!

2025-12-17 15:31:17
推荐回答(2个)
回答1:

1+2+3=3*4/2
1+2+3+4=4*5/2
1+2+3+4+5=5*6/2
……
1+2+3+4+……+100=100*101/2
所以,
1 +1/1+2 +1/1+2+3 +1/1+2+3+4……+1/1+2+3+4...100
=1/2(1/2+1/2*3+1/3*4+1/4*5+……+1/100*101)
=1/2(1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+……+1/100-1/101)
=1/2(1-1/101)
=50/101

回答2:

1 +1/1+2 +1/1+2+3 +1/1+2+3+4……+1/1+2+3+4...100
=1+1/3+1/6+1/10+……+
=2(1-1/2)+2(1/2-1/3)+2(1/3-1/4)+……+2(1/100-1/101)
=2[1-1/2+1/2-1/3+1/3-1/4+……+1/100-1/101]
=2(1-1/101)
=2*100/101
=200/101