Select the correct choice that completes the sentence below. The sum formula for tangent function is $\tan (\alpha+\beta)=$

Step 1 ：The sum formula for tangent function is a well-known trigonometric identity. It is given by the formula: \(\tan (\alpha+\beta) = \frac{\tan \alpha + \tan \beta}{1 - \tan \alpha \tan \beta}\). This formula is derived from the sum formulas for sine and cosine functions.

Step 2 ：Final Answer: \(\boxed{\tan (\alpha+\beta) = \frac{\tan \alpha + \tan \beta}{1 - \tan \alpha \tan \beta}}\)