(a-b)≤[{b+(a-b)}/2]^2=(a/2)^2,
当且仅当b=a-b,即a=2b时等号成立.
则原式≥a^2+64/(a^2)≥2[(a^2){64/(a^2)}]^(1/2)=16,
当且仅当a^4=64,即a=2√2,b=√2时,最小值为16.
(a-b)≤[{b+(a-b)}/2]^2=(a/2)^2,
当且仅当b=a-b,即a=2b时等号成立.
则原式≥a^2+64/(a^2)≥2[(a^2){64/(a^2)}]^(1/2)=16,
当且仅当a^4=64,即a=2√2,b=√2时,最小值为16.