Please help. Differential Calculus

1. Given f (x) = 5x2, show, from first principles, that f' (x) = 10x. Note: This problem is to be solved using limits. Do not simply use differentiation rules. 2. Given f (x) = sin(3x) esx, find f' (x). 3. Given f (x) = sin x x+1 find f' (x). 4. Use implicit differentiation to find - given x2 + y2 = 15 5. Use logarithmic differentiation to find the derivative of y = (tan x)". 6. A car rental company charges its customers p dollars per day, where 60