先化简,再求值 1、5ac-2a^2b+[3abc-（4ab^2-a^2b）],其中a=-2,b=-1,c=3.5ac-2a^2b+3abc-4ab^2+a^2b=5ac-a^2b+3abc-4ab^2当a=-2,b=-1,c=3时,5ac-a^2b+3abc-4ab^2=5×(-2)×3-(-2)^2×(-1)+3×(-2)×(-1)×3-4×(-2)×...