内容正文:
高三数学(文科)答案 第 1 页 共 6 页
2017届高三定时测试
数学(文科)参考答案及评分标准
一、选择题:本大题共 10小题,每小题 5分,共 50分.
CABB DCAA CB
二、填空题:本大题共 5小题,每小题 5分,共 25分.
11.
1
4
12.
1[ 1, ]
5
− 13. OCD BCDS S⋅△ △ 14. 2 15.4
三、解答题:本大题共 6小题,共 75分.
16.解:解:(1)由分层抽样可知,抽取比例为
6 1=
9+18+27 9
;
因此,应从“文学社”、“围棋社”、“书法社”这三个社团中抽取的人数分别为 1,
2,3. ··························································································································· 4分
(2)①从 6人中随机的抽出 2人组成活动小组的所有可能结果为{ 1A , 2A },{ 1A , 3A },
{ 1A , 4A },{ 1A , 5A },{ 1A , 6A },{ 2A , 3A },{ 2A , 4A },{ 2A , 5A },{ 2A , 6A },
{ 3A , 4A },{ 3A , 5A },{ 3A , 6A },{ 4A , 5A },{ 4A , 6A },{ 5A , 6A },共有 15种可
能的结果. ···················································································································· 8分
②编号为 1A 和 2A 的 2人中恰有 1人被抽到的所有可能结果为{ 1A , 3A },{ 1A , 4A },
{ 1A , 5A },{ 1A , 6A },{ 2A , 3A },{ 2A , 4A },{ 2A , 5A },{ 2A , 6A },共有 8种.
因此,事件 A发生的概率 8( )
15
P A = . ······································································· 12分
注:按有顺序的依次抽取 2人,只要结果正确,同样给分.
17.解:(1) ( ) 3sin 2 (1 cos2 )f x x x= − − ································································· 2分
π2sin(2 ) 1.
6
x= + − ············································································· 3分
因为
π π
6 3
x− < < ,所以 π π 5π2 .
6 6 6
x− < + < ······················································ 4分
所以
1 πsin(2 ) 1
2 6
x− < + � ,所以 π2 2sin(2 ) 1 1.
6
x− < + − �
所以函数 ( )f x 在 π(
6
− ,
π )
3
上的值域为 ( 2− ,1]. ·········································· 6分
高三数学(文科)答案 第 2 页 共 6 页
(2)由 ( ) 0f C = ,得 π2sin(2 ) 1 0
6
C + − = ,即 π 1sin(2 ) .
6 2
C + =
在 ABC△ 中,0 πC< < , π π 13π2
6 6 6
C< + < .
所以
π 5π2
6 6
C + = ,即 π
3
C = .············································································ 8分
所以
2π
3
A B+ = ,即 2π
3
B A= − .
因为 sin sin sinB A C= ,所以 2π 3sin( ) sin
3 2
A A− = ,
所以
2π2sin( ) 3sin
3
A A− = ,即 3 cos sin 3sin .A A A+ =
所以