Question

Cos 50 18"=0.6388 and cos 50 42"=0.6334 find cos 50 20"

Answer 1

Answer:

0.6384

Step-by-step explanation:

Cos 50 18" - Cos 50 42" = 0.6388 - 0.6334 =  0.0054.

So difference for 24" = 0.0054

    difference for 2" = 0.0054/12 = 0.00045.

Hence Cos 50 20" = 0.6388 - 0.00045 = 0.63835

                                                                 = 0.6384