Tanα/2
问题描述:
Tanα/2
答
tana/2=sina/2 / cosa/2
=2sina/2*cosa/2 / 2cos^2a/2
=sina/(1+cosa)
tana/2=sina/2 / cosa/2
=2sin^2a/2 /2sina/2cosa/2
=(1-cosa)/sina