MATHEMATICS · Multi-part · AoPS · Mathematics · Special Functions · Special Functions
Problem
Define the function f(x)=5−x+1.
(i) State the separate algebraic conditions that must simultaneously hold for f(x) to be real-valued.
(ii) Solve these conditions to obtain the domain of f, writing your answer as a single interval or union of intervals.
(iii) Verify by substitution that every endpoint of the domain you obtained actually makes f(x) real.