若xy互为相反数,求x+2x+3x+...+100x+100y+99y+98y+,+2y+y的值
问题描述:
若xy互为相反数,求x+2x+3x+...+100x+100y+99y+98y+,+2y+y的值
答
因为x,y互为相反数x+y=0
x+2x+3x+...+100x+100y+99y+98y+,+2y+y
=(x+y)+2(x+y)+3(x+y)+...+100(x+y)
=0