⑴连接AD,ΔABC是等腰直角三角形,
∴AD⊥BC,∠DAB=∠C=45°,AD=CD,
∵DE⊥DF,∴∠ADE+∠ADF=∠ADF+∠CDF=90°,
∴∠ADE=∠CDF,∴ΔADE≌ΔCDF(ASA),
∴DE=DF.
⑵AE=AB-BE=2-X,由⑴知,AE=CF,
∴Y=2-X(0
⑴连接AD,ΔABC是等腰直角三角形,
∴AD⊥BC,∠DAB=∠C=45°,AD=CD,
∵DE⊥DF,∴∠ADE+∠ADF=∠ADF+∠CDF=90°,
∴∠ADE=∠CDF,∴ΔADE≌ΔCDF(ASA),
∴DE=DF.
⑵AE=AB-BE=2-X,由⑴知,AE=CF,
∴Y=2-X(0