並前往https://www.facebook.com/hkgeogebra/posts/domain-range-of-a-function-%E5%87%BD%E6%95%B8%E7%9A%84%E5%AE%9A%E7%BE%A9%E5%9F%9F%E5%92%8C%E5%80%BC%E5%9F%9Fhttpswwwgeogebraorgmzzyaz56d/763604173794233/