with detailed solution 2 only

2. [10 pts] Find all the third partial derivatives (if exist) of f(I, y, z) = rarctan(eTy=) + 3:"y sec(Inx y). 3. [10 pts each] Identify any extrema of the function by recognizing its given form or its form after completing the square. Verify your results by using the partial derivatives to locate any