log1/2^x≥2,求x?

log1/2^x≥2,求x?
log1/2^x≥2,求x?

log1/2^x≥2,求x?
log1/2^x≥2=log1/2^1/4
log1/2^x递减
真数大于0
所以0

（0,0.25）

0≤x ≤ 1/4