化简,求值

显示全部楼层 · 2008-11-2 16:34:00

8M平方-2(3M+4M平方-1)-8其中-1
2A平方B-[2AB平方-2(A平方B+2AB平方)]其中A=-1\2,B=1

千问 · 2008-11-2 16:34:00

8M^2-2(3M+4M^2-1)-8=8M^2-6M-8M^2+2-8=-6M-6=-6*(-1)-6=6-6=02A^2B-[2AB^2-2(A^2B+2AB^2)]=2A^2B-2AB^2+2(A^2B+2AB^2)=2A^2B-2AB^2+2A^2B+4AB^2=4A^2B+2AB^2=4*(-1/2)^2*1+2*(-1/2)*1^2=4*(1/4)-2*(1/2)=1-1=0...