f(x) = 3x - 2 Domain: all x in (-∞,∞)
f(x) = sqrt(x + 2) Domain: x≥-2, all x in [-2,∞)
f(x) = 4 - x^2 Domain: all x in (-∞,∞)
f(x) = 1/(x-3) Domain: x≠3, all x in {(-∞,3) (3,∞)}
f(x) = x^3 - 2x - 1 Domain: all x in (-∞,∞)
f(x) = sqrt(9-x^2) Domain: 9-x2≥0, x2≤9, -3≤x≤3, all x in [-3,3]
f(x) = 1 + 1/x Domain: x≠0, all x in {(-∞,0) (0,∞)}
f(x) = 1/(x^2-x-6) Domain: x2-x-6≠0, (x-3)(x+2)≠0, x≠3, x≠-2, all x in {(-∞,-2) (-2,3) (3,∞)}