■解答
① \(\displaystyle\frac{mg}{k}\) ② \(k(A_0-x)\) ③ \(2\pi\sqrt{\displaystyle\frac{m}{k}}\)
④ 位相 ⑤ \(\sqrt{\displaystyle\frac{k}{m}(A_0^2-x^2)}\) ⑥ \(\displaystyle\frac{1}{3}\)
⑦ 略 ⑧ \(2\) ⑨ \(-ev_1\)
⑩ \(\displaystyle\frac{A_0}{2}\sqrt{1+3e^2}\)