a) a₂ = a₁ * q = 3.2 * 0.5 = 1.6
б) a₄ = a₁ * q³ = 3.2 * (0.5)³ = 3.2 * 0.125 = 0.4
в) a₇ = a₁ * q⁶ = 3.2 * (0.5)⁶ = 3.2 * 0.015625 = 0.05
г) aₖ₊₁ = a₁ * qᵏ = 3.2 * (0.5)ᵏ