中学生网络课堂本课配套习题挑战模式1/5
单选题
难度系数：
1.已知等差数列
中，
，
，则该数列前9项和
等于
中，，，则该数列前9项和等于 | A: 55 |
| B: 45 |
| C: 35 |
| D: 25 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOebtOaOpeS7o+WFpeWFrOW8jzxpbWcgd2lkdGg9MTE2IGhlaWdodD00MiBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzkwLzJEL3JCQUNGRlNqb0R1Q2dsWmNBQUFDMkV5UTU5ZzAxMC5wbmciPg==
- 答案：Qg==
5oqKPGltZyB3aWR0aD00MCBoZWlnaHQ9MjEgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC82My8yNi9yQkFDRTFTam9EcWczakVyQUFBQmI1bWtVbjg3NjUucG5nIj7vvIw8aW1nIHdpZHRoPTgzIGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzJGLzIyL3JCQUNKbFNqb0R2eUVUb09BQUFCLVQtbFBIUTk2MS5wbmciPuS7o+WFpeWFrOW8jzxpbWcgd2lkdGg9MTE2IGhlaWdodD00MiBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzkwLzJEL3JCQUNGRlNqb0R1Q2dsWmNBQUFDMkV5UTU5ZzAxMC5wbmciPu+8jOW+lzxicj7lhazlvI88aW1nIHdpZHRoPTE3NyBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AxLnFpbmdndW8uY29tL0cxL00wMC8yRi8yMi9yQkFDSmxTam9EdmlOcFA1QUFBRExickFlZWsyMzcucG5nIj4u5pWF6YCJQi4=
本课配套习题挑战模式2/5
单选题
难度系数：
2.已知等差数列中，
，则该数列前9项和等于
中，，则该数列前9项和等于 | A: 18 |
| B: 27 |
| C: 36 |
| D: 45 |
一次做对，真牛！
+5奖励规则>
- 提示1：IDxpbWcgd2lkdGg9MTA4IGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzYzLzI2L3JCQUNFMVNqb0VHQjJDZHFBQUFDQWZ4N19MNDc0Ny5wbmciPg==
- 提示2：IDxpbWcgd2lkdGg9OTUgaGVpZ2h0PTQyIHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvOTAvMkQvckJBQ0ZGU2pvRUhBczBpT0FBQUNYUkNDQ1RRNzU1LnBuZyI+
- 答案：Qw==
4oi1PGltZyB3aWR0aD0xMzQgaGVpZ2h0PTIxIHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvMkYvNjAvckJBQ0oxU2pvRUdna1FwRkFBQUNQM29TRERnMDkxLnBuZyI+77yM5Luj5YWlPGltZyB3aWR0aD0xODAgaGVpZ2h0PTQyIHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvNjMvMjYvckJBQ0UxU2pvRUhTR2NZaEFBQURScExDckpVNDczLnBuZyI+5omA5Lul6YCJQy4=
本课配套习题挑战模式3/5
单选题
难度系数：
3.设
是等差数列的前
项和，已知
,则
是等差数列的前项和，已知,则 | A: 13 |
| B: 35 |
| C: 49 |
| D: 63 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOeUsTxpbWcgd2lkdGg9MTAyIGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzJGLzIyL3JCQUNKbFNqb0VtanJWU2pBQUFCLUt0bmt3UTM4NC5wbmciPuiuoeeul+WHujxpbWcgd2lkdGg9OSBoZWlnaHQ9MjEgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC8yRi82MC9yQkFDSjFTam9FbmhBQklYQUFBQk5OMlhKcGcxNzIucG5nIj4u
- 提示2：IOS7o+WFpeetieW3ruaVsOWIl+WJjTxpbWcgd2lkdGg9OCBoZWlnaHQ9MjEgc3JjPSJodHRwczovL3AxLnFpbmdndW8uY29tL0cxL00wMC85MC8yRC9yQkFDRkZTam9FbUFQUjNkQUFBQk15N1JoXzQ0MzEucG5nIj7pobnlkozlhazlvI88aW1nIHdpZHRoPTExNiBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC85MC8yRC9yQkFDRkZTam9EdUNnbFpjQUFBQzJFeVE1OWcwMTAucG5nIj4=
- 答案：RA==
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
本课配套习题挑战模式4/5
单选题
难度系数：
4.设
是等差数列
的前
项和，若
,则
是等差数列的前项和，若,则 | A: 8 |
| B: 7 |
| C: 6 |
| D: 5 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOe7k+WQiOetieW3ruS4remhueaxguinow==
- 答案：RA==
4oi1PGltZyB3aWR0aD05NiBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC82My8yNi9yQkFDRTFTam9GamdfdHkyQUFBQ2JJMllhY2s4MTIucG5nIj7vvIzogIw8aW1nIHdpZHRoPTg1IGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzkwLzJEL3JCQUNGRlNqb0ZpaVg5U2lBQUFDQXdtWHU5NDExOC5wbmciPu+8jDxicj7iiLQ8aW1nIHdpZHRoPTg3IGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzJGLzIyL3JCQUNKbFNqb0ZpaW9pZEZBQUFDS215anNJVTAzMi5wbmciPu+8jDxicj7iiLQ8aW1nIHdpZHRoPTQzIGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzJGLzIyL3JCQUNKbFNqb0ZqaUpkV29BQUFCb1pSQ2c2TTgxMS5wbmciPuaVhemAiUQu
本课配套习题挑战模式5/5
单选题
难度系数：
5.在等差数列中，已知
中，已知 | A: 40 |
| B: 42 |
| C: 43 |
| D: 45 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOagueaNruW3suefpeadoeS7tuaxguWHuuWFrOW3rjxpbWcgd2lkdGg9OSBoZWlnaHQ9MjEgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC8yRi82MC9yQkFDSjFTam9FbmhBQklYQUFBQk5OMlhKcGcxNzIucG5nIj4=
- 提示2：IOinguWvn+imgeaxgueahOW8j+WtkO+8jOi/m+ihjOWMlueugA==
- 答案：Qg==
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
