(3)(4x-2y)-[5x-(8y-2x-y)]+x (4)-(2x²-3x-1)-2(x²-3x+5)+(x²+4x+3)

问题描述:

(3)(4x-2y)-[5x-(8y-2x-y)]+x (4)-(2x²-3x-1)-2(x²-3x+5)+(x²+4x+3)

(4x-2y)-[5x-(8y-2x-y)]+x
=4x-2y-5x+8y-2x-y+x
=-2x+6y
-(2x²-3x-1)-2(x²-3x+5)+(x²+4x+3)
=-2x²+3x+1-2x²+6x-10+x²+4x+3
=-3x²+13x-6