Question

find the value of cos 74 39'

Answer 1

( Cos 90 - A ) = Sin A

Here A = 74

( Cos 90 - 74 ) = Sin 16 .

Cos 74 ===> Sin 16

( Cos 90 - B ) = Sin B

Here B = 39

( Cos 90 - 39 ) = Sin 51

Cos 39 ===> Sin 51