Question

Following are APs or not? If they form an A.P. find the common difference d and write three more terms: 

2, 4, 8, 16 … 

Answer 1

2, 4, 8, 16 …

Here,

a₂ - a₁ = 4 - 2 = 2

a₃ - a₂ = 8 - 4 = 4

a₄ - a₃ = 16 - 8 = 8

⇒ a_k+1 - a_k is not the same every time.

Therefore, The given numbers do not form an AP.