HELLO I Want help in these questions

show all your work and briefly explain your steps & reasoning (reason for doing the work you are showing).

1) Differentiate & fully simplify the following functions:

In this question I want help in number b and when solving I want to know what are you doing each step in words. so each time you do a step explain to me what u did to have a better understanding of the answer given,

b.) f (x) = 3csc' (2x) sec'(3x)4.) Given f(x) = 41:24:" a.) Determine the points at which x) has horizontal tangents algebraically. b.) Are there places on x) in which f(x) is not differentiable? Explain. 2.) Determine of y = tan 4x dx2