I'm working on manipulating trig identities and using Wolfram Alpha to check the identity still holds.
I'm going from this:
$\frac{1-\cos x}{1+\cos x} = \frac{1}{tan^2x}-\frac{2}{\tan x \sin x} + \frac{1}{\sin^2 x}$
which WA verifies is an identity to this:
$\frac{1+\cos x}{1-\cos x} = tan^2x-\frac{\tan x \sin x}{2} + \sin^2 x$
which WA seems to think is only true for certain values of x.
Based on my workings out on paper, I think I'm safe in flipping both sides. Wonder if someone might weigh in on this to help me out please?