(2)如图,连接OE,PC.
S四边形OPEG?S?OEG?S?OPE?S?OEG??S?OPC?S?PCE?S?OEC?
141415315??(4?t)?3?[?3?(8?t)??(8?t)?t??3?(8?t)] 252524524315??t2?t?6(0?t?5). 88
(3)存在.
35267QS??(t?)2?(0?t?5),
8232?t?
(4)存在.如图,连接OQ. QOE?OQ,
??EOC??QOC?90?, Q?QOC??QOG?90?,
5267时,四边形OPEG的面积最大,最大值为. 232??EOC??QOG,?tan?EOC?tan?QOG, ECGQ, ?OCOG35t8?t4?5,
434?t5
整理得:5t2?61t?160?0,
解得t?61?52161?521或t??5(舍弃)
1010当t?
61?521秒时,OE?OQ. 10
相关推荐: