正确!
1.0.999999...=9/9=1
2.0.999999...=0.33333...*3=1/3*3=1
3.0.999999...=limit(0.9+0.09+0.009+0.0009+...)=ans(1)=1
4 0.999999...=d/dx 1+1=[0.99999...]'+1=1
正确!
1.0.999999...=9/9=1
2.0.999999...=0.33333...*3=1/3*3=1
3.0.999999...=limit(0.9+0.09+0.009+0.0009+...)=ans(1)=1
4 0.999999...=d/dx 1+1=[0.99999...]'+1=1