Question

The nth term of a sequence is given by 2n+1.
Write down the first four terms of the sequence.​

Answer 1

x, 2x+1, 4x+3, 8x+7

Explanation:

If we call the first term x, then the subsequent term is 2x+1. Then, the next term is 2(2x+1)+1=4x+2+1=4x+3. Then, the fourth term is 2(4x+3)+1=8x+6+1=8x+7.

As a matter of fact, the nth term is given by
`2^(n-1)x+2^(n-1)-1` for starting term x.