Let abc be a real number, and simplify |a|+a=0|ab|=ab|c|-c=0 Simplify | B |-A+B |-C-B |+A-C | Analysis |a|+a=0, that is | A | =-AA ≤ 0; | ab | = abab≥0b≤0； |c|-c=0 means |c|=cc≥0. Original formula =-b+a+b-c+b-a+c=b Known: (a+b)? +|b+5|=b+5| 2 a-b- Find the ab value according to |=0. The flat absolute value and some non-negative zeros are analyzed, so every number is zero. 0(a+b)？ +b+5=b+5, which means (a+b)? = 0 ...① Er a-b- Yi = 0...② Solution a= Yi/San b=- Yi/San ab=- Yi/