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> 在△ABC中，记∠BAC=x（角的单位是弧度制），△ABC的面积为S，且 AB • AC =8，4≤S≤4 3 ．（1）求x的取值范围；（2）就（1）中x的取值范围，求函数 f(x)=2 3 sin2(x+ π 4 )+2cos2x- 3 的最大值、最小值．

问题：

发布时间：2024-09-09

在△ABC中，记∠BAC=x（角的单位是弧度制），△ABC的面积为S，且

AB

•

AC

=8，4≤S≤4

3

．
（1）求x的取值范围；
（2）就（1）中x的取值范围，求函数 f(x)=2

3

sin2(x+

π

4

)+2cos2x-

3

的最大值、最小值．

参考答案：

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在△ABC中，记∠BAC=x（角的单位是弧度制），△ABC的面积为S，且 AB • AC =8，4≤S≤4 3 ． （1）求x的取值范围； （2）就（1）中x的取值范围，求函数 f(x)=2 3 sin2(x+ π 4 )+2cos2x- 3 的最大值、最小值．

可能感兴趣的题目：

在△ABC中，记∠BAC=x（角的单位是弧度制），△ABC的面积为S，且

AB

•

AC

=8，4≤S≤4

3

．
（1）求x的取值范围；
（2）就（1）中x的取值范围，求函数 f(x)=2

3

sin2(x+

π

4

)+2cos2x-

3

的最大值、最小值．