简便计算 (18 19:5:39)
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简便计算 (18 19:5:39)
(1+0.12+0.23)X(0.12+0.23+0.34)-(1+0.12+0.23+0.34)X(0.12+0.23)
如果A▲B=3A-2B ,求2▲( 3▲4 )
(1+0.12+0.23)X(0.12+0.23+0.34)-(1+0.12+0.23+0.34)X(0.12+0.23)
如果A▲B=3A-2B ,求2▲( 3▲4 )
1.原式=1*(0.12+0.23+0.34)+(0.12+0.23+0.34)*(0.12+0.23)-
[1*(0.12+0.23)+(0.12+0.23)*(0.12+0.23+0.34)]
= (0.12+0.23+0.34)+(0.12+0.23+0.34)*(0.12+0.23)-
(0.12+0.23)-(0.12+0.23)*(0.12+0.23+0.34)
= (0.12+0.23+0.34)-(0.12+0.23)
=0.34
2.3▲4=3*3-2*4=1
2▲( 3▲4 ) = 2▲1=3*2-2*1=4
[1*(0.12+0.23)+(0.12+0.23)*(0.12+0.23+0.34)]
= (0.12+0.23+0.34)+(0.12+0.23+0.34)*(0.12+0.23)-
(0.12+0.23)-(0.12+0.23)*(0.12+0.23+0.34)
= (0.12+0.23+0.34)-(0.12+0.23)
=0.34
2.3▲4=3*3-2*4=1
2▲( 3▲4 ) = 2▲1=3*2-2*1=4