1.綜合運(yùn)用
如圖1,在平面直角坐標(biāo)系中,正方形OABC的頂點(diǎn)A在x軸的正半軸上.如圖2,將正方形OABC繞點(diǎn)O逆時(shí)針旋轉(zhuǎn),旋轉(zhuǎn)角為α(0°<α<45°),AB交直線y=x于點(diǎn)E,BC交y軸于點(diǎn)F.
(1)當(dāng)BE=BF時(shí),旋轉(zhuǎn)角∠COF為
度;
(2)若點(diǎn)C(-2,4),求點(diǎn)B坐標(biāo)與BF的長(zhǎng);
(3)如圖3,對(duì)角線AC交y軸于點(diǎn)M,交直線y=x于點(diǎn)N,連接FN.若FN=ON,將△OCN與△OAN的面積分別記為S
1與S
2.設(shè)S=S
1-S
2,CO=m,CF=n,請(qǐng)猜想S、m與n的數(shù)量關(guān)系,并說明理由.