Question

tan(45)=tan(30)+tan(15)?

Answer 1

Are you supposed to be using the tan(A + B) or tan(A - B) to solve this? I am going to assume that you are. So let's go with that. I just taught this to my Trig class last week! There is a certain way in which to look at this type of problem, which is in terms of angles for which we have known values, like 30, 60, 90, and 45. So in this problem, the way we can get to 45 is tan (90 - 45). Now I can show you the difficult way to do this which involves a lengthy formula, or I can draw you the angle in the plane and get you to the answer in a simpler way. Let me draw both and you can decide!. See that? You could use the formula and you would get the exact same thing!