Question

Determine if given expression is a function. If so, find out if it is one to one, onto or bijection.
(a) Given f: Z → Z+, f(x) = |x − 2| + 1.
(b) Given f: Z → Z+, f(x) = −3x + 2.
(c) Given f: R→ R, f(x) = x² − 2x + 1.