Why does the trigonometric Pythagorean theorem works outside the unit circle? I thought the the Pythagorean identity "$sin^2+cos^2 = 1$" was derived inside the unit circle when the hypotenuse of the triangle was one. So why does this formula work outside of the unit circle? Does the calculator just always assumes that the hypotenuse is one? Would it work if the hypotenuse wasn't one?
Thanks in advance.

Every triangle outside the unit circle is basically the same as one on the unit circle.

i.e., we can always scale it down and $\sin^2+\cos^2=1$ holds all the way.
