I need to know how to go about #7.
2n - 99 > 0 ⇒ 2n > 99 ⇒ n > 99/2 ⇒ n > 49.5 ⇒ n ≥ 50.So, the first positive term is :t₅₀ = 2·50 - 99 = 100 - 99 = 1 > 0