Expand sin(A±B), cos(A±B), and tan(A±B) using the sum and difference identities. Enter two angles in degrees to see the full substitution and result with verification.
sin(A±B) = sin A cos B ± cos A sin B
cos(A+B) = cos A cos B − sin A sin B
cos(A−B) = cos A cos B + sin A sin B
tan(A±B) = (tan A ± tan B) / (1 ∓ tan A tan B)
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