6【x-y】-2[x+y]-4[x-y]+4[x+y]
问题描述:
6【x-y】-2[x+y]-4[x-y]+4[x+y]
化简
答
=6(x-y)-4(x-y)+4(x+y)-2(x+y)
=2(x-y)+2(x+y)
=2x-2y+2x+2y
=4x