Answer:
Step-by-step explanation:
Premise: If n is a positive integer, then 11ⁿ-6 is divisible by 5.
Let n=1.
11¹-6 = 5, so the premise is true for n=1.
Suppose the premise is true when n is an integer greater than 1,
then 11ⁿ-6 is divisible by 5.
11ⁿ⁺¹-6 = 11·11ⁿ - 6
= (10+1)11ⁿ - 6
= (10·11ⁿ) + (1·11ⁿ) - 6
= (10·11ⁿ) + (11ⁿ - 6)
Both terms are divisible by 5, so 11ⁿ⁺¹-6 is divisible by 5. Therefore, the premise holds true for n+1.
Proof by induction.
