07/10/06 20:16:46
>>438
(sinθ)^3 / (tanθ)^2 = (sinθ)(cosθ)^2 = (sinθ){1-(sinθ)^2}
= 2/(3√3) - {(2/√3) + sinθ}{(1/√3) - sinθ}^2 ≦ 2/(3√3),
(tanθ)^2 ≧ {(3√3)/2}(sinθ)^3,
等号成立は sinθ = 1/√3 のとき。
07/10/06 20:16:46
>>438
(sinθ)^3 / (tanθ)^2 = (sinθ)(cosθ)^2 = (sinθ){1-(sinθ)^2}
= 2/(3√3) - {(2/√3) + sinθ}{(1/√3) - sinθ}^2 ≦ 2/(3√3),
(tanθ)^2 ≧ {(3√3)/2}(sinθ)^3,
等号成立は sinθ = 1/√3 のとき。