Find the principal values of `cosec^(-1)(-sqrt2)`

Explanation

To find the principal values of \( \csc^{-1}(-\sqrt{2}) \), we can follow these steps:

### Step 1: Set up the equation
Let \( \theta = \csc^{-1}(-\sqrt{2}) \). This implies:
\[ \csc(\theta) = -\sqrt{2} \]

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