Solve `tanx+tan2x+tan3x=tanxtan2xtan3x ,x in [0,pi]`

Explanation

To solve the equation \( \tan x + \tan 2x + \tan 3x = \tan x \tan 2x \tan 3x \) for \( x \) in the interval \( [0, \pi] \), we will follow these steps:

### Step 1: Rewrite the equation
We start with the given equation:
\[ \tan x + \tan 2x + \tan 3x = \tan x \tan 2x \tan 3x \]

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