急急急急~~求求各位亲了 已知a>0,b<0且IbI>a,化简Ia+bI-Ia-bI-I-a-bI-Ib-aI=?
急急急急~~求求各位亲了 已知a>0,b<0且IbI>a,化简Ia+bI-Ia-bI-I-a-bI-Ib-aI=?
日期:2011-01-09 20:26:30 人气:1
Ia+bI-Ia-bI-I-a-bI-Ib-aI
= b-a -(a-b)-(-b+a)-(a-b)
= b-a -a +b +b -a -a +b
= -4(a+b)
急急急急~~求求各位亲了 已知a>0,b<0且IbI>a,化简Ia+bI-Ia-bI-I-a-bI-Ib-aI=?