24.在Rt△ABC中,∠ACB=90°,CA=CB,點(diǎn)O為AB的中點(diǎn),點(diǎn)D在直線AB上(不與點(diǎn)A,B重合),連接CD,線段CD繞點(diǎn)C逆時(shí)針旋轉(zhuǎn)90°,得到線段CE,過點(diǎn)B作直線l⊥BC,過點(diǎn)E作EF⊥l,垂足為點(diǎn)F,直線EF交直線OC于點(diǎn)G.
(1)如圖1,當(dāng)點(diǎn)D與點(diǎn)O重合時(shí),請(qǐng)直接寫出線段AD與線段EF的數(shù)量關(guān)系;
(2)如圖2,當(dāng)點(diǎn)D在線段AB上時(shí),求證:CG+BD=
BC;
(3)連接DE,△CDE的面積記為S
1,△ABC的面積記為S
2,當(dāng)EF:BC=1:3時(shí),請(qǐng)直接寫出
的值.