Use to give the tangent of an angle.
In a right angled triangle, the tangent of an angle is the length of the opposite side (O) divided by the length of the adjacent side (A).
tanx = O/A
So for an example we could transpose the formula to find either A or O if we know the angle x.
O = A * tanx or A = O/tanx
In the software we would enter the following for the values where A is 15 and O is 26 and x is 60 degrees
=(TAN(60))*15 and =26/(TAN(60))