Question
Question: If \(\pi < \alpha < \frac{3\pi}{2}\), then \(\sqrt{\frac{1 - \cos\alpha}{1 + \cos\alpha}} + \sqrt{\f...
If π<α<23π, then 1+cosα1−cosα+1−cosα1+cosα=
A
sinα2
B
−sinα2
C
sinα1
D
−sinα1
Answer
−sinα2
Explanation
Solution
1+cosα1−cosα+1−cosα1+cosα=1−cos2α1−cosα+1+cosα
=±sinα2=−sinα2,(since π<α<23π).