Can someone explain the following diagram I have drawn.
For example where the t and 2 came from and their use in identities as I cannot make the relationship between them in trig identities involving tan
Using pythagorean theorem you can see the relationship between the sides.
Where A is the hypotenuse (across from the 90 degree angle) and B and C are the vertical and horizontal sides.
The right side is a perfect square and thus simplifies to:
Rooting both side we see A, the hypotenuse, is
Does this clarify things for you?