Answers:

(i)

f(x) is defined for all real values of x, except when x + 1 = 0 or x = –1.

∴ Domain of f = R – {–1}

(ii)

f (x) is defined for all real values of x, except when x² – 9 = 0.

x² – 9 = 0

x² – 3² = 0

(x + 3)(x – 3) = 0

x + 3 = 0 or x – 3 = 0

x = ± 3

∴ Domain of f = R – {–3, 3}