µÈÄú»ØÀ´Ó´¡«
Äú¼´½«À뿪Ìù°ÉÌøתµ½ÈçÏÂÍøÖ·£¬¸ÃÍøַδÔÚÌù°ÉÈ·Èϵݲȫ·¶Î§ÄÚ£¬ÇëÌáÇ°È·ÈÏÄúµÄÒþ˽°²È«ºóÌøת¡£
http://elecbyte.com/alpha/trig^¬
¼ÌÐø·ÃÎÊ