if `tan^(-1)(4/3)=theta`, find the value of `costheta`.

Explanation

To find the value of \( \cos \theta \) given that \( \tan^{-1}\left(\frac{4}{3}\right) = \theta \), we can follow these steps:

### Step 1: Identify \( \tan \theta \)
From the given information, we have:
\[ \tan \theta = \frac{4}{3} \]

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