来自容太平的问题
-(3a+2b)+(4a-3b+1)-(2a-b-3)的结果是多少?
-(3a+2b)+(4a-3b+1)-(2a-b-3)的结果是多少?
3回答
2020-03-24 08:49
-(3a+2b)+(4a-3b+1)-(2a-b-3)的结果是多少?
-(3a+2b)+(4a-3b+1)-(2a-b-3)的结果是多少?
-(3a+2b)+(4a-3b+1)-(2a-b-3)
=-3a-2b+4a-3b+1-2a+b+3
=(-3+4-2)a+(-2-3+1)b+1+3
=-a-4b+4
(x+y-z)+(x-y+z)-(x-y-z)是多少?
(x+y-z)+(x-y+z)-(x-y-z)=x+y-z+x-y+z-x+y+z=(1+1-1)x+(1-1+1)y+(-1+1+1)z=x+y+z