- If \(\tan A=\tan B\), what can we say about \(A\) and \(B\)?

What about the corresponding questions for sine and cosine?

If \(\cos A=\cos B\), what can we say about \(A\) and \(B\)?

If \(\sin A=\sin B\), what can we say about \(A\) and \(B\)?

Suggestion: Think about the graphs of the trigonometric functions!