We are given the equation \( \tan \left( \frac{\pi}{12} + 2x \right) = \cot 3x \).
Using the identity \( \cot \theta = \frac{1}{\tan \theta} \), we get: \[ \tan \left( \frac{\pi}{12} + 2x \right) = \frac{1}{\tan 3x} \] Multiplying both sides by \( \tan 3x \), we get: \[ \tan \left( \frac{\pi}{12} + 2x \right) \tan 3x = 1 \] Now solve for \( x \) by substituting values: \[ x = \frac{\pi}{12} \]
If $ X = A \times B $, $ A = \begin{bmatrix} 1 & 2 \\-1 & 1 \end{bmatrix} $, $ B = \begin{bmatrix} 3 & 6 \\5 & 7 \end{bmatrix} $, find $ x_1 + x_2 $.