x{3x-[(x+2y)-(2x-y)]}+5,求大师们速速回答!要有正确的解题方法!
问题描述:
x{3x-[(x+2y)-(2x-y)]}+5,求大师们速速回答!要有正确的解题方法!
答
x{3x-[(x+2y)-(2x-y)]}+5
=x[3x-(x+2y-2x+y)]+5
=x(3x+x-3y)+5
=4x²-3xy+5