For θ∈[0,2π], consider the composite expression arcsin(sinθ).
a. (i) Determine the value of arcsin(sinθ) when θ∈[0,2π]. Justify your answer with reference to the principal value branch.
b. (ii) Calculate arcsin(sin67π) and arcsin(sin45π) showing each step clearly.
c. (iii) Derive a piece-wise definition of arcsin(sinθ) for all θ in the interval [0,2π]. Provide clear reasoning for the interval break-up used.