Let f(x)=3−2x and g(x)=x+1, where the square roots denote principal (non-negative) values. Answer the following questions.
a. (i) Find the domain of f and the domain of g.
b. (ii) Determine the domain of the sum function (f+g)(x).
c. (iii) Justify, with reference to the defining rules of f and g, why every element outside the set obtained in part (ii) must be excluded from the domain of (f+g)(x).