1949×(1/51-1/2000)+51×(1949-1/2000)-2000×(1/1949+1/51)+3

问题描述:

1949×(1/51-1/2000)+51×(1949-1/2000)-2000×(1/1949+1/51)+3

1949*(1/51-1/2000)+51*(1/1949-1/2000)-2000*(1/1949+1/51)+3
=1949/51-1949/2000+51/1949-51/2000-2000/1949-2000/51
=(1949/51-2000/51)+(51/1949-2000/1949)-(1919/2000+51/1949)+3
=-51/51-1949/1949-2000/2000+3
=-1-1-1+3
=0