並前往http://spaces.isu.edu.tw/~poychen/2008_1C_Calculus/%E9%99%B3%E6%9F%8F%E7%A9%8E%E5%BE%AE%E7%A9%8D%E5%88%86_ch2_%E5%B0%8E%E5%87%BD%E6%95%B8-%E9%A1%8C%E7%9B%AE%E5%85%A7%E5%AE%B9.pdf