Question

Sin alpha/1-cos alpha +sin alpha/1+cos alpha=4

Answer 1

Answer :

alpha = 30°

sin alpha [ (1+cos alpha) + sin alpha (1-cos alpha) ] ÷ 1-cos^2 alpha = 4

[ sin alpha ( 1+cos alpha + 1 - cos alpha ) ] ÷ sin^2 alpha = 4

*key : sin^2 alpha + cos^2 alpha = 1

1+1+ cos alpha - cos alpha = 4 sin alpha

2 = 4 sin alpha

1 = 2 sin alpha

sin alpha = ½

*alpha = 30°