m²-1/2<=0(m+√2/2)(m-√2/2)<=0所以-√2/2<=m<=√2/2
m的绝对值小于等于2分之根号二，m小于等于二分之根号二大于等于负二分之根号二
解答：m²≤1/2的解：-√2/2≤m≤√2/2
就说明 负二分之根号二《M《二分之根号二 啊
