Question

What are the first five terms of the sequence generated by the formula below?

Answer 1

Answer:

The correct option is:

2, 4, 12, 48, 240

Step-by-step explanation:

We have to determine the first 5 terms of the sequence by using following formula:

$a_n=2n!$

To Calculate the first 5 terms.

Put n = 1

a₁ = 2 (1)!

a₁ = 2(1)

a₁ = 2

Put n = 2

a₂ = 2 (2)!

a₂ = 2 (2·1) = 2(2)

a₂ = 4

Put n = 3

a₃ = 2(3)!

a₃ = 2(3·2·1)

a₃ = 2(6)

a₃ = 12

Put n = 4

a₄ = 2(4)!

a₄ = 2(4·3·2·1)

a₄ = 2(24)

a₄ = 48

Put n =5

a₅ = 2(5)!

a₅ = 2(5·4·3·2·1)

a₅ = 2(120)

a₅ = 240