送交者: lars 于 2007-04-13, 17:11:05:

回答: 两边求导，一下子就得出 x = b 由 xinku 于 2007-04-13, 17:02:34:

• sorry. misunderstanding........... (无内容) - xinku (0 bytes) 2007-04-13, 17:31:59 (135458)

加跟贴