y=log2^(x^2-ax+1)有最小值,求a的取值范围

y=log2^(x^2-ax+1)有最小值,求a的取值范围
y=log2^(x^2-ax+1)有最小值,求a的取值范围

y=log2^(x^2-ax+1)有最小值,求a的取值范围
只需想x^2-ax+1>0恒成立
得-2