Hello, omgilymcr!

We will need these identities:

. .

. .

. .

. .

The first fraction is: .

. . . . . . . . . .

The second fraction is: .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

We see that [2] is the negative of [1].

Therefore, their sum is zero.

Edit: corrected typo.

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