1/5单选题
难度：
1.
如图，在△ABC中，AD⊥BC于D，若AB2=BD•BC，则下列结论成立的是（ ）
| A |
|
| B | AB⊥AC |
| C |
|
| D | AD+DC=AB |
•AB- 提示1：
- PHA+55Sx5Zyo4pazQUJD5Lit77yMQUTiiqVCQ++8jOWPr+W+l+KIoEFEQj05MMKw77yM5Y+I55SxQUI8c3VwPjI8L3N1cD49QkTigKJCQ++8jOaYk+ivgeW+l+KWs0FCQ+KIveKWs0RCQe+8jOWImeWPr+W+l+KIoENBQj3iiKBBREI9OTDCsDwvcD4=
正确答案：Qg==
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
2/5单选题
难度：
2.
如图，在△ABC中，AD⊥BC于D，∠ABC=2∠C，则下列结论中一定成立的是（ ）
| A | AC2=AB2+AB•BC |
| B |
|
| C |
|
| D |
|
- 提示1：
- PHA+5Li65LqG5oqK4oigQUJDPTLiiKBD6L2s5YyW5oiQ5Lik5Liq6KeS55u4562J55qE5p2h5Lu277yM5Y+v5Lul5p6E6YCg6L6F5Yqp57q/77ya5ZyoREPkuIrlj5ZERT1CRO+8jOi/nuaOpUFFLjwvcD4=
- 提示2：
- PHA+5qC55o2u57q/5q6155qE5Z6C55u05bmz5YiG57q/55qE5oCn6LSo5Lul5Y+K5LiJ6KeS5b2i55qE5YaF6KeS5ZKM5a6a55CG55qE5o6o6K666IO95aSf6K+B5piOQUI9Q0UuIOWGjeagueaNruWLvuiCoeWumueQhuihqOekuuWHukFDPHN1cD4yPC9zdXA+77yMQUI8c3VwPjI8L3N1cD4uIOWGjei/kOeUqOS7o+aVsOS4reeahOWFrOW8j+i/m+ihjOiuoeeul+WwseWPr+ivgeaYji48L3A+
正确答案：QQ==
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
3/5单选题
难度：
3.
如图，Rt△ABC中，∠ACB=90°，AC=4，BC=6，以斜边AB上的一点O为圆心所作的半圆分别与AC、BC相切于点D、E，则AD为（ ）
| A | 2.5 |
| B | 1.6 |
| C | 1.5 |
| D | 1 |
- 提示1：
- PHA+6L+e5o6lT0TjgIFPRe+8jOWFiOiuvkFEPXjvvIzlho3or4HmmI7lm5vovrnlvaJPRENF5piv55+p5b2i77yM5Y+v5b6X5Ye6T0Q9Q0XvvIxPRT1DRO+8jOS7juiAjOW+l+WHukNEPUNFPTQteO+8jEJFPTYt77yINC1477yJ77yM5Y+v6K+B5piO4pazQU9E4oi9T0JF77yM5YaN55Sx5q+U5L6L5byP5b6X5Ye6QUTnmoTplb/ljbPlj68uPC9wPg==
正确答案：Qg==
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
4/5单选题
难度：
4.
如图，C、D为半圆O上的两点，OC⊥AB，OC=5，AD=8，则OP的值为（ ）
| A | 2 |
| B |
|
| C |
|
| D |
|
- 提示1：
- PHA+6L+e57uTQkTvvIzmoLnmja7lnIblkajop5LlrprnkIblvpfiiKBBREI9OTDCsO+8jOWGjeagueaNruWLvuiCoeWumueQhuiuoeeul+WHukJEPTbvvIznhLblkI7or4HmmI7ilrNBUE/iiL3ilrNBQkTvvIzlho3liKnnlKjnm7jkvLzmr5Tlj6/orqHnrpflh7pPUC48L3A+
正确答案：RA==
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
5/5单选题
难度：
5.
如图，AD是△ABC的高，AB=15，AC=12，AD=10，则△ABC的外接圆直径AE长为（ ）
| A | 20 |
| B | 18 |
| C | 16 |
| D | 10 |
- 提示1：
- 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
正确答案：Qg==
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