若m=2,则-1>0,不成立,符合解集为空集若m=-2,则-4x-1>0,解集不是空集若m≠±2,则这时二次不等式,大于0的解集为空集所以(m^2-4)x^2+(m-2)x-1<=0恒成立则开口向下,m^2-4<0,(m+2)(m-2)<0,-2且判别式小于等于0(m-2)^2+4(m^2-4)<=0(m-2)^2+4(m+2)(m-2)<=0(m-2)[(m-2)+4(m+2)]<=0(m-2)(5m+6)<=0-6/5<=m<=2要符合-2所以-6/5<=m<2综上-6/5≤m≤2