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如图,⊙O内切于△ABC,切点分别为D,E,F、已知∠B=50°,∠C=60°,...
如图,⊙O内切于△ABC,切点分别为D,E,F、已知∠B=50°,∠C=60°,连接OE,OF,DE,DF,那么∠EDF等于
.
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