72X0.81 10.4怎么简便计算
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0.027+9.9x0.27=0.27×0.1+9.9×0.27=0.27×(0.1+9.9)=0.27×10=2.7
7.56+0.12x0.9+0.44=(7.56++0.44)+0.12x(1-0.1)=8+0.12-0.012=8.12-0.012=8.108
72*0.9*0.9+10.4再问:列递式再答:0.8*0.9*0.9*0.9+0.8*13=(0.9*0.9*0.9+13)*0.8=(0.072+13)*0.8再问:不对再答:哦哦0.8*90*0
12.5-12.5×0.2=12.5×1-12.5×0.2=12.5×(1-0.2)=12.5×0.8=10
2.8×0.5+1.58=1.4+1.58=1.4+1.6-0.02=3-0.02=2.98
再答:如果满意请采纳谢谢
有简便方法,方法如下:根据(x-0.1)^3=x^3-0.3x^2+0.03x-0.001,把x=1代入即得,原式=1-0.3+0.03-0.001=0.729
这个没法简算52.5x0.63+3.7x0.5=33.075+1.85=34.925
1.25x0.7x0.8=(1.25×0.8)×0.7=1×0.7=0.7再问:那9.8x25呢
1.25x0.25x0.05x64=1.25x0.25x0.05x8×8=1.25x8x0.25x(0.05x8)=10x0.25x0.4=2.5x0.4=1
=2.6*1+0.264-0.26=2.6-0.04=2.56
8.45X0.27+8.45X0.63+0.845=8.45X0.27+8.45X0.63+0.845x1=8.45X0.27+8.45X0.63+8.45x0.1=8.45X(0.27+0.63+0
3.8x2.7+38x0.73=3.8x2.7+(3.8x10)x0.73=3.8x2.7+3.8x(10x0.73)=3.8x2.7+3.8x7.3=3.8x(2.7+7.3)=3.8x10=38
25.25*0.65*4/0.65=(25.25*4)*(0.65/0.65)=101*1=101
102x0.35=(100+2)x0.35=100x0.35+2x0.35=35+0.7=35.7
25.25x0.64x4/0.64=25.25x4=25x4+0.25x4=100+1=101