由题意得a+b=0 cd=1 |m|=√2 则m=√2或-√2
故当m=√2时,a+b+1/cd×(1-2m+m^2)=0+1*(1-2√2+2)=3-2√2
当m=-√2时,a+b+1/cd×(1-2m+m^2)=0+1*(1+2√2+2）=3+2√2
故……