Question

List the first three elements of the set
x = 3n, n a positive integer

Answer 1

`x \in \{3, 6, 9 \}`

Explanation:

Given:

`\x`

The first three elements of the given set are just the values of
`x` when
`n = 1, 2, 3`.

Solving for
`x` when
`n = 1`:

`x = 3n \\ x = 3(1) \\ x = 3`

Solving for
`x` when
`n = 2`:

`x = 3n \\ x = 3(2) \\ x = 6`

Solving for
`x` when
`n = 3`:

`x = 3n \\ x = 3(3) \\ x = 9`

Answer 2

{3,6,9}

Step-by-step explanation:

first element = 3×1

second element = 3×2

third element = 3×3

Explanation: