×î½üÈϿɳöÁËÕâô¼¸ÖÖ£¬´óÖ·ÖΪȺÖÚÈϿɺÍÉϼ¶ÈϿɡ£ÈºÖÚÈϿɶȸߣ¬ËµÄãÓÐÄÜÁ¦£¬ÄÇ˵Ã÷ÄãÓÐÇ׺ÍÁ¦£¬ÒªÃ´ÓпØÖÆÈºÖÚµÄ×ÊÔ´¡£Éϼ¶ÈϿɶȸߣ¬ËµÄãºÜÓÐÏë·¨£¬ÄÇ˵Ã÷ÄãÓÐÄÜÁ¦£¬ÄÜΪÉϼ¶×ö¹±Ïס£×ÜÖ®ÈϿɶȲ»ÂÛ±°¼ú£¬²»ÊÇ˵×ÝÏòÈϿɶȾͱȺáÏòÈϿɶȸ߼¶£¬¶øÊÇ˵£¬Äã¶ÔË£¬¶ÔÄÄÒ»ÀàȺÌåÇ×½ü£¬²¢²»ÊÇ˵¶ÔÄÄÒ»ÀàȺÌåÓÐÓã¬¶ËÆðÍëÀ´³ÔÈâ·ÅÏÂÍëÀ´ÂîÄïµÄʲ»ÔÚÉÙÊý¡£
Ç×½üÄÄÒ»À࣬ÄÄÒ»ÀàȺÌå¾ÍÈÏ¿ÉÄã¡£ÎïÒÔÀà¾Û£¬ÈËÒÔȺ·Ö¡£Ã¤Ä¿Ñ°ÕÒÈϿɣ¬ÓÐʱºòÊÇÄÏÔ¯±±ÕÞ£»ÓÐÈË×ìêñ£¬ËµÄǵØÇò»¹ÊÇÔ²µÄÄØ¡£ÄÇÒ²²»ÊDz»ÐУ¬ÓеÄÈËÉú¾ÍÊÇÕâÑù±ëº·£¬Ò²¾ÍÊÇ˵£¬ÔõôÑù¶¼ÐУ¬×ÜÖ®ÒªÈȰ®Éú»î¡£
ÈÏ¿É(1/2),µã»÷ÏÂÒ»Ò³¼ÌÐøÔĶÁ