-(2a-5b)-{-3b-2[4a-2(3a-b)]}
问题描述:
-(2a-5b)-{-3b-2[4a-2(3a-b)]}
答
-(2a-5b)-{-3b-2[4a-2(3a-b)]}
=-2a+5b+3b+2(4a-6a+2b)
=-2a+8b-4a+4b
=-6a+12b