If A + B + C = `180^(@)`, then prove that tan A + tan B + tan C = tan A tan B tan C.

Explanation

To prove that if \( A + B + C = 180^\circ \), then \( \tan A + \tan B + \tan C = \tan A \tan B \tan C \), we can follow these steps:

### Step 1: Use the identity for tangent of a sum
Since \( A + B + C = 180^\circ \), we can express \( C \) in terms of \( A \) and \( B \):
\[ C = 180^\circ - (A + B) \]

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