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如图,AB是⊙O的直径,AB=4,AC是弦,AC=,∠AOC=( ) A.120...
如图,AB是⊙O的直径,AB=4,AC是弦,AC=
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,∠AOC=( )
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A.120°
B.130°
C.140°
D.150°
考点分析:
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