对于有理数x,y,x※y=3x+2y 则[(x+y)※(x-y)] ※3x=()
问题描述:
对于有理数x,y,x※y=3x+2y 则[(x+y)※(x-y)] ※3x=()
答
[(x+y)※(x-y)] ※3x
=[3(x+y)+2(x-y)]※3x
=(5x+y)※3x
=3*(5x+y)+2*3x
=15x+3y+6x
=21x+3y