Cos A = 0.83 and cos B = 0.55. What is sin A + sin B?

If the cos A =.83 then the arc cosine of. 83 equals the angle

arc cosine (.83) = 33.901 degrees

Similarly, we look up the arc cosine of. 55

arc cosine (.55) = 56.633 degrees

NOW we can look up the sine of 33.901 degrees and find it is the

sine of A and it equals 0.55776

the sine of 56.633 degrees = 0.83516 and that is the sine of B