Domain
SAT glossary · Math
Definition
The set of inputs the machine accepts. On this exam only two things restrict it: a denominator cannot be zero (excluding isolated points, not a ray), and an even root cannot take a negative radicand (requiring radicand ≥ 0). That is the entire list — polynomials and odd roots restrict nothing.
Domain in plain English
The domain of a function is simply the full list of inputs it's allowed to accept without breaking. On this test, there are really only two ways an input can get banned: dividing by zero is never allowed, so any input that would make a denominator equal zero gets kicked out (but this only removes that one specific number, not a whole stretch of numbers); and you can never take an even root (like a square root) of a negative number and get a real answer, so whatever's under an even root must be zero or positive. That covers the entire list of restrictions tested — regular polynomial functions (no fractions, no roots) never have any domain restrictions at all, and neither do odd roots like cube roots, which are perfectly happy accepting negative numbers.
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