$$xyz\,=1$$
$$x+ x^{-2}\leqq 2\,(yz+ x)^{2}+ k$$
$$k= -\frac{127}{32}- \frac{1}{32\sqrt{\frac{3}{8195+ w}}} + \frac{1}{2}\sqrt{\frac{1}{128}\left ( \frac{8195}{3}- \frac{w}{6}+ 32\,767\sqrt{\frac{3}{8195+ w}} \right )}$$
$$w= 8\,\sqrt[3]{1091\,430\,712- 787\,080\,\sqrt{98\,385}}+ 16\,\sqrt[3]{136\,428\,839+ 98\,385\,\sqrt{98\,385}}$$
Bài viết đã được chỉnh sửa nội dung bởi DOTOANNANG: 10-05-2018 - 17:39