作者Huawen (开心就好~)
看板tutor
标题Re: [解题] 国三 圆
时间Sun Sep 4 04:57:19 2011
http://ppt.cc/wVt4
__ __ __ __
设 OD = OA = r 且 AB = OC = 5
__ __
则 CD = √(r^2 - 5^2 ) = OE
__ __
又 OE + OA = 10
则 √(r^2 - 5^2 ) + r = 10
r = 25/4
圆面积 = (25/4)^2 * π
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 175.181.227.65