Răspuns:
x₂ = 3
Explicație pas cu pas:
logₓ₊₂(x²-1) = logₓ₊₂(x+5)
Conditii:
x²-1 > 0 x² > 1 => x ∈ (-∞ ; -1) ∪ (1 ; +∞)
x+5 > 0 => x > -5
x+2 > 0 => x > -2
x+2 ≠ 1 => x ≠ -1 =>
x ∈ (1 ; +∞) =>
x²-1 = x+5 => x²-x-6 = 0 => x₁,₂ = [1±√(1+24)]/2 =>
x₁,₂ = (1±5)/2 => x₁ = -2 nu convine; x₂ = 3
