Functions f and g are defined by
f:x2x-3. XER.
g:x+r+4r. XER.
(i) Solve the equation ff(x) = 11.
(ii) Find the range of g.
(iii) Find the set of values of x for which g(x) > 12.
(iv) Find the value of the constant p for which the equation gf(x) = p has two equal roots.
Function h is defined by h : x x + 4x for x >k, and it is given that h has an inverse.
(v) State the smallest possible value of k.
(vi) Find an expression for h'(x).