17/08/27 00:47:52.80 NetfQ0ow.net
>>677 (3) >>690 >>694
・t≧9 のときは明らか。
・3≦t≦9 のとき。
24tt -(9-t)(t^3 +9uu)= t(t-3)^3 +3(9-t)(t-3)≧ 0,
(9-t)/3t ≦ 8t/(t^3 +9uu),
(左辺)-(右辺)=(2/s + 1/3)- 3/t
= 2/(su) - (9-t)/3t
≧ 2/(su) -8t/(t^3 +9uu)
= 2(t^3 -4stu +9uu)/{su(t^3 +9uu)}
= 2uu・F_1(1/x,1/y,1/z)/{s(t^3 +9uu)}
≧ 0,