1、-1-1 1.3 3.3 3已知三角函数值求角-2-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航1.掌握已知三角函数值求角的方法,会由已知的三角函数值求角,并会用符号arcsin x,arccos x,arctan x表示角.2.熟记一些常见的三角函数值及其在区间-2,2上对应的角.-3-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOU
2、XI典例透析MUBIAODAOHANG目标导航123答案:A-4-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123答案:D-5-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航1232.已知余弦值,求角对于余弦函数y=cos x,如果已知函数值y(y-1,1),那么在0,上有唯一的x值和它
3、对应,记作x=arccos y(-1y1,0 x).答案:A-6-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123-7-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123答案:B-8-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SU
4、ITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123-9-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航-10-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航同样可知等式arccos(cos x)=x成立的条件是x0,;通过剖析可知,只要弄
5、清楚上述几个等式分别成立的条件,则对于各类试题中经常出现的这类问题就可正确迅速地求解.-11-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航-12-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航2.已知三角函数值求角的基本类型剖析-13-1.3.3已知三角函数值求角ZHISHI SHULI知
6、识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航-14-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航归纳总结归纳总结 已知角的一个三角函数值求角,实际上是解一个最简单的三角方程.一般说来,所得的解不是唯一的,而是有无数多个.当然角的个数受范围的约束,这一点需引起重视.若求得的角是特殊角,最好用弧度制表示;若是非特殊角,题目没要求求出具体角的值,
7、则不用查表,而是用含arcsin x,arccos x,arctan x的式子表示即可.-15-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三分析借助正弦函数的图象及所给角的范围求解.-16-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-17-1.3.3
8、已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-18-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-19-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI
9、典例透析MUBIAODAOHANG目标导航题型一题型二题型三分析借助余弦函数的图象及所给角的范围求解.-20-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-21-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-22-1.3.3已知三角函数值求角ZHISH
10、I SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-23-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三【例3】已知tan=-3.(2)若0,2,求角;(3)若R,求角.分析借助正切函数的图象及所给角的范围求解.-24-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN
11、JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-25-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航题型一题型二题型三-26-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123456答案:C-27
12、-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123456答案:C-28-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123456答案:D-29-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIAN
13、LI TOUXI典例透析MUBIAODAOHANG目标导航123456-30-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航1234565.若arccos(2x-1)有意义,则x的取值范围是.解析:要使arccos(2x-1)有意义,则需-12x-11,即0 x1,故x0,1.答案:0,1-31-1.3.3已知三角函数值求角ZHISHI SHULI知识梳理ZHONGNAN JVJIAO重难聚焦SUITANGYANLIAN随堂演练DIANLI TOUXI典例透析MUBIAODAOHANG目标导航123456
