1/6单选题
难度：
1.如图所示，在⊙O中，
=
，∠A=30°，则∠B=（ ）
=，∠A=30°，则∠B=（ ） | A | 150° |
| B | 75° |
| C | 60° |
| D | 15° |
- 提示1：
- IOWFiOagueaNruetieW8p+aJgOWvueeahOW8puebuOetieaxguW+l0FCPUFD77yM5LuO6ICM5Yik5a6a4pazQUJD5piv562J6IWw5LiJ6KeS5b2i77yb54S25ZCO5qC55o2u562J6IWw5LiJ6KeS5b2i55qE5Lik5Liq5bqV6KeS55u4562J5b6X5Ye64oigQj3iiKBD77yb5pyA5ZCO55Sx5LiJ6KeS5b2i55qE5YaF6KeS5ZKM5a6a55CG5rGC6KeSQueahOW6puaVsOWNs+WPry4=
正确答案：Qg==
6Kej77ya4oi15Zyo4oqZT+S4re+8jDxpbWcgd2lkdGg9MjggaGVpZ2h0PTI0IHNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvQTIvRDQvckJBQ0UxT1gteHF3N09GT0FBQUJwakZaUUpZNjk4LnBuZyI+ID08aW1nIHdpZHRoPTI5IGhlaWdodD0yNSBzcmM9Imh0dHBzOi8vcDEucWluZ2d1by5jb20vRzEvTTAwL0EyL0Q0L3JCQUNFMU9YLXh2aHhTdGNBQUFCcVRiTVJGYzU1MC5wbmciPu+8jDxicj7iiLRBQj1BQ++8jDxicj7iiLTilrNBQkPmmK/nrYnohbDkuInop5LlvaLvvIw8YnI+4oi04oigQj3iiKBD77ybPGJyPuWPiOKIoEE9MzDCsO+8jDxicj7iiLTiiKBCPTc1wrA8YnI+5pWF6YCJQi4g
2/6单选题
难度：
2.如图，已知：AB是⊙O的直径，C、D是
上的三等分点，∠AOE=60°，则∠COE是（ ）
上的三等分点，∠AOE=60°，则∠COE是（ ） | A | 40° |
| B | 60° |
| C | 80° |
| D | 120° |
- 提示1：
- IOWFiOaxguWHuuKIoEJPRT0xMjDCsO+8jOWGjei/kOeUqOKAnOetieW8p+WvueetieinkuKAneWNs+WPr+inoy4=
正确答案：Qw==
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
3/6单选题
难度：
3.如图，AB和CD是⊙O的两条直径，弦DE∥AB，弧DE为50°的弧，那么∠BOC为（ ）
| A | 115° |
| B | 100° |
| C | 80° |
| D | 50° |
- 提示1：
- IOi/nuaOpU9F77yM5qC55o2u5bynREXkuLo1MMKw77yM5rGC5Ye64oigRU9EPTUwwrDvvIzmoLnmja5PRT1PRO+8jOaxguWHuuKIoE9FRD3iiKBPREU9NjXCsO+8jOagueaNrkRF4oilQULvvIzmsYLlh7riiKBBT0U94oigT0VEPTY1wrDvvIziiKBBT0Q94oigQU9FK+KIoEVPRD02NcKwKzUwwrA9MTE1wrDvvIzmnIDlkI7moLnmja7iiKBCT0M94oigQU9E5Y2z5Y+v5rGC5Ye6562U5qGILg==
正确答案：QQ==
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
4/6单选题
难度：
4.如图，AB、CD是⊙O的两条弦，OE⊥AB于E，OF⊥CD于F. 如果AB=CD，那么下列判断中错误的是（ ）
| A |  |
| B | ∠AOB=∠COD |
| C | OE=OF |
| D | ∠AOC=∠BOD |
- 提示1：
- IOeUsU9F4oqlQULvvIxPRuKKpUNE77yM5aaC5p6cQUI9Q0TvvIzmoLnmja7lnKjlkIzlnIbmiJbnrYnlnIbkuK3vvIzikaDlnIblv4Pop5Lnm7jnrYnvvIzikaHmiYDlr7nnmoTlvKfnm7jnrYnvvIzikaLmiYDlr7nnmoTlvKbnm7jnrYnvvIzkuInpobnigJznn6XkuIDmjqjkuozigJ3vvIzkuIDpobnnm7jnrYnvvIzlhbbkvZnkuozpobnnmobnm7jnrYnvvIzljbPlj6/liKTlrppB5LiOQuato+ehru+8mw==
- 提示2：
- IOeEtuWQjuWIqeeUqOWeguW+hOWumueQhuS4juWFqOetieS4ieinkuW9ouaAp+i0qO+8jOWNs+WPr+WIpOWumkPmraPnoa4uIOazqOaEj+aOkumZpOazleWcqOino+mAieaLqemimOS4reeahOW6lOeUqC4=
正确答案：RA==
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
5/6单选题
难度：
5.如图，△ABC内接于⊙O，D为线段AB的中点，延长OD交⊙O于点E，连接AE，BE，则下列五个结论①AB⊥DE，②AE=BE，③OD=DE，④∠AEO=∠C，⑤
，正确结论的个数是（ ）
，正确结论的个数是（ ） | A | 2 |
| B | 3 |
| C | 4 |
| D | 5 |
- 提示1：
- IOW3suefpU9F5piv4oqZT+eahOWNiuW+hO+8jETmmK/lvKZBQueahOS4reeCue+8jOWPr+agueaNruWeguW+hOWumueQhueahOaOqOiuuuadpeWIpOaWreaJgOe7meWHuueahOe7k+iuuuaYr+WQpuato+ehri4=
正确答案：Qg==
6Kej77ya4oi1T0XmmK/iiplP55qE5Y2K5b6E77yM5LiUROaYr0FC55qE5Lit54K577yMPGJyPuKItE9F4oqlQULvvIw8aW1nIHdpZHRoPTExOCBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AxLnFpbmdndW8uY29tL0cxL00wMC82Ni9CMi9yQkFDRkZPWC14X1NuMFJ2QUFBRFdRMmVxcFU4NjAucG5nIj7vvIjmlYXikaDikaTmraPnoa7vvIk8YnI+4oi0QUU9QkXvvJvvvIjmlYXikaHmraPnoa7vvIk8YnI+55Sx5LqO5rKh5pyJ5p2h5Lu26IO95aSf6K+B5piO4pGi4pGj5LiA5a6a5oiQ56uL77yM5omA5Lul5LiA5a6a5q2j56Gu55qE57uT6K665piv4pGg4pGh4pGk77ybPGJyPuaVhemAiUIuIA==
6/6单选题
难度：
6.如图，AB是⊙O的直径，BC、CD、DA是⊙O的弦，且BC=CD=DA，则∠BCD=（ ）
| A | 105° |
| B | 120° |
| C | 135° |
| D | 150° |
- 提示1：
- IOi/nue7k09E44CBT0M=
- 提示2：
- IOeUsUJDPUNEPURBLOWPr+W+l+KIoEFPRD3iiKBDT0Q94oigQ09CPTYwwrA=
- 提示3：
- IOS4ieinkuW9okFPQuOAgUNPROOAgUJPQ+mDveaYr+etiei+ueS4ieinkuW9og==
正确答案：Qg==
6Kej77ya6L+e57uTT0TjgIFPQzxicj7nlLFCQz1DRD1EQSzlj6/lvpfiiKBBT0Q94oigQ09EPeKIoENPQj02MMKwPGJyPuKItU9BPU9EPU9DPU9CPGJyPuKItOS4ieinkuW9okFPQuOAgUNPROOAgUJPQ+mDveaYr+etiei+ueS4ieinkuW9ojxicj7iiLTiiKBCQ0Q9MTIwwrA8YnI+6YCJQg==