Câu hỏi 25
Tìm $W^2-2W$, trong đó
$$W=\frac{\sqrt{100+\sqrt1}+\sqrt{100+\sqrt2}+\cdots+\sqrt{100+\sqrt{9999}}}{\sqrt{100-\sqrt1}+\sqrt{100-\sqrt2}+\cdots+\sqrt{100-\sqrt{9999}}}.$$
$$W=\frac{\sqrt{100+\sqrt1}+\sqrt{100+\sqrt2}+\cdots+\sqrt{100+\sqrt{9999}}}{\sqrt{100-\sqrt1}+\sqrt{100-\sqrt2}+\cdots+\sqrt{100-\sqrt{9999}}}.$$