已知Rt△ABC中,∠ACB=90度,CA=CB,有一個圓心角為45度,半徑的長等于CA的扇形CEF繞
已知Rt△ABC中,∠ACB=90度,CA=CB,有一個圓心角為45度,半徑的長等于CA的扇形CEF繞
數(shù)學(xué)人氣:608 ℃時間:2019-08-22 14:48:08
優(yōu)質(zhì)解答
CEF繞C點旋轉(zhuǎn),E,F在斜邊AB上,線段AE,EF,FB總可以構(gòu)成直角三角形.證明:將△CAE繞C逆時針旋轉(zhuǎn)90°,A點和B點重合,E點到P,連PF,△CAE≌△CBP.∴BP=AE,又CP=CE,∠ECF=∠PCF=45°,CF是公共邊,∴△CEF≌△CPF,(S,A,S)∴E...
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