If `cos A=4/(5), cosB=12/13` and `(3pi)/2 < A, B < 2pi` then find the value of `cos(A+B)`

Explanation

To find the value of \( \cos(A + B) \) given that \( \cos A = \frac{4}{5} \) and \( \cos B = \frac{12}{13} \) with the angles \( A \) and \( B \) in the range \( \frac{3\pi}{2} < A, B < 2\pi \), we will follow these steps:

### Step 1: Determine the values of \( \sin A \) and \( \sin B \)

Since \( A \) and \( B \) are in the fourth quadrant, we know that \( \sin A \) and \( \sin B \) will be negative.

1. **Calculate \( \sin A \)**:
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