已知Y满足不等式 Y+1/2 -Y>2+ Y+2/3,化简[Y+1]+[2Y-1] [ ]符号用来代替绝对值的符号
问题描述:
已知Y满足不等式 Y+1/2 -Y>2+ Y+2/3,化简[Y+1]+[2Y-1] [ ]符号用来代替绝对值的符号
答
(Y+1)/2-Y大于2+(Y+2)/3
(Y+1-2Y)/2大于(6+Y+2)/3
3(1-Y)大于2(8+Y)
3-3Y大于16+2Y
5Y小于-13
Y小于-13/5
则Y+1小于0,2Y-1小于0
则|Y+1|+|2Y-1|=-Y-1-2Y+1=-3Y