=1.1×1.1(1.1-1)-1.1×0.1=1.1×0.1×(1.1-1)=0.01
1.1x(1.1x1.1-1.1)-0.11=1.1x0.11-0.11=0.121-0.11=0.011
1.1*（1.21-1.1.-0.1）=1.1*0.01=0.011
