Urgent calculus help needed?

this is just simple calculus, for question 1, u just need know the exponential differentiation and the chain rule by putting the first part into index form. For question 2, u need to know that (d/dx (tan x)= sec^2 x) and then sec^2 4xcan be separated into (1+tan^2 4x), then u just differentiate it using letting u = cos x. Then for 4, use implicit differentiations. For 3, u just need to know the trig property (cosec^2 -1)= cot^2, then u can differentiate from that point onwards. not sure if this will help