並前往http://www.nhmath.com/NH-MATH/images/%E9%AB%98%E4%B8%AD%E5%85%B1%E5%82%99%E6%89%8B%E5%86%8A/04%20%E6%8C%87%E6%95%B8%E8%88%87%E5%B0%8D%E6%95%B8.pdf
