Using the formula, 
, find the value of sin 30°, it being given that cos 60° = 
Given: sin A = 
, …………………….(1)
cos 60° = 1/2
To find: sin 30°
By putting A = 30° in equation (1), we get the following:
sin 30° = 
= 
= 
= 1/2
∴ sin 30° = 1/2
19
Using the formula, , find the value of sin 30°, it being given that cos 60° =
Given: sin A = , …………………….(1)
cos 60° = 1/2
To find: sin 30°
By putting A = 30° in equation (1), we get the following:
sin 30° =
=
= = 1/2
∴ sin 30° = 1/2