Q19 of 27 Page 301

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


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