並前往https://math.ymhs.tyc.edu.tw/chenjt99/ScrClass/1042/HomWok/Book2/%E7%BF%92%E4%BD%9C%E7%94%B2%E7%AC%AC1%E7%AB%A0%20%E7%B6%9C%E5%90%88%E6%BC%94%E7%B7%B4.pdf