函数log2(4x)乘log4(4/x^2)>=2

函数log2(4x)乘log4(4/x^2)>=2

(log2(4)+log2(x))*(log4(4)-log4(x^2))>=2
(2+log2(x))*(1-log2(x))>=2
2-2*log2(x)+log2(x)-(log2(x))^2>=2
-log2(x)-(log2(x))^2>=0
log2(x)+(log2(x))^2<=0
log2(x)*(1+log2(x))<=0
log2(x)*log2(2x)<=0
在数轴上标根、穿线,即得
0.5<=x<=1
∴x∈[0.5,1]
(*为乘号,^为乘方)