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延長CE至G,連接AC交BD於點O,在正方形ABCD中,因為BD為AC的垂直平分線,且E為BD上一點,EA=EC,∴∠EAO=∠ECO,又∵∠DAO=∠DCO,∴∠DCE=∠DAF∵∠DCB=90°,∴∠ECB=90°-25°=65°.∴∠BEC=180°-∠ECB-∠EBC=1…
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