-3.14*35.2+6.28*（-23.3）-1.57*36.4
=-(3.14*35.2+6.28*23.3+1.57*36.4)
=-[3.14*35.2+3.14*2*23.3+(3.14/2)*36.4]
=-3.14*(35.2+46.6+18.2)
=-3.14*100
=-314
也可以提1.57为公因子,一样的.