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已知,如图,在△ABC中,∠B=90°,AB=BC,AE是∠BAC的角平分线,CD⊥AE交AE的延长线于D.求证:CD=1\2AE
人气:205 ℃ 时间:2020-06-05 10:04:09
解答
证明:延长AB交CD的延长线于点F∵∠ABC=90而∠ABC+∠CBF=180∴∠CBF=90=∠ABC又∵CD垂直AE于D∴∠ADC=∠ADF=∠ABC=90又∵∠ABC+∠BAD+∠AEB=180∠ADC+∠BCF+∠CED=180而∠AEB=∠CED∴∠BAD=∠BCF用∠BAD=∠BCF,...
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