Please answer the following questions:

Q3: (a) Use the identity tan( A + B)= tan A + tan B 1-tan Atan B to express tan 2x in terms of tan x. (2) (b) Show that 2- 2tan x- 2 tan x (1-tan x) tan 2x for all values of x, tan 2x # 0. (4) (Total 6 marks) Q4: (a) Given that y = x* tan 2x, use the product rule find (3) (b) Using the quotient rule, find the gradient of the curve with equation at the point where x = 3. x-1 (3) (Total 6 marks)