Răspuns:
Explicație pas cu pas:
a) f(x) = √(x-5) => x-5 ≥ 0 => x ≥ 5 => x ∈ [5 ; +∞)
d) f(x) = ⁴√(7-4x) => 7-4x ≥ 0 => 4x ≤ 7 => x ≤ 7/4 =>
x ∈ (-∞ ; 7/4]
g) f(x) = (2-3x) / √(2x-6) => 2x-6 > 0 => 2x > 6 =>
x > 3 => x ∈ (3 ; +∞)
j) f(x) = 2019/(3-⁴√x) =>
x ≥ 0 ; ⁴√x ≠ 3 => x ≠ 81 => x ∈ [0 ; +∞)-{81}
