1.58*0.58+0.42*0.42+1.16*0.42怎样简算 1.58*0.58+0.42*0.42+1.16*0.42怎样简算

1.58*0.58+0.42*0.42+1.16*0.42
=(1+0.58)*0.58+0.42*0.42+1.16*0.42
=0.58+(0.58*0.58+0.42*0.42+2*0.58*0.42)
=0.58+(0.58+0.42)^2
=0.58+1^2
=1.58

1.58*0.58+0.42*0.42+1.16*0.42
=1.58*0.58+0.42*（0.42+1.16）
=1.58*0.58+0.42*1.58
=1.58*（0.58+0.42）
=1.58*1
=1.58