Calculator needed, or if you have an ol' fashioned math book with tables
in the back ....
Calc:
press
2ndF
cos
0.2493
=
you should get 75.56390633..°
round off to the suggested accuracy, e.g. 1 decimal
B = 75.6°
BUT...
the cosine is positive in quadrants I and IV , (know the CAST rule)
so B = 360-75.6 ° = 284.4°
in your book, find the closest to .2493 in the column of cosines
Unless you know how to do interpolation, the best you can do is 76°
Cos B = 0.2493
solve
1 answer