tanA=2,1/(sin^2A-cos^2A)=

分类: 作业答案 • 2022-01-09 18:01:45

问题描述：

答

tana=2
1/(sin^2a-cos^2a)
=(sin^2a+cos^2a)/(sin^2a-cos^2a)
=(tan^2a+1)/(tan^2a-1)
=(5)/(3)