Question

3. What are the first four terms of the sequence represented by the expression n(n –1) – 5? (1 point)

– 7, –5, –3, 1
– 5, –10, –15, –20
0, 2, 6, 12
– 5, –3, 1, 7

Answer 1

Option D: The first 4 terms of the sequence is -5, -3, 1, 7

Step-by-step explanation:

Given that the expression is
`n(n-1)-5`

We need to determine the first 4 terms of the sequence.

The first 4 terms of the sequence can be determined by substituting n = 1, 2, 3, 4

1st term of the sequence:

Substituting n = 1 in the expression
`n(n-1)-5`, we have,

`1(1-1)-5`

Simplifying, we get,

`1(0)-5=-5`

Thus, the 1st term of the sequence is -5

2nd term of the sequence:

Substituting n = 2 in the expression
`n(n-1)-5`, we have,

`2(2-1)-5`

Simplifying, we get,

`2(1)-5\implies2-5\implies-3`

Thus, the 2nd term of the sequence is -3.

3rd term of the sequence:

Substituting n = 3 in the expression
`n(n-1)-5`, we have,

`3(3-1)-5`

Simplifying, we get,

`3(2)-5\implies 6-5\implies 1`

Thus, the 3rd term of the sequence is 1.

4th term of the sequence:

Substituting n= 4 in the expression
`n(n-1)-5`, we have,

`4(4-1)-5`

Simplifying, we get,

`4(3)-5\implies 12-5\implies 7`

Thus, the 4th term of the sequence is 7

Thus, the first 4 terms of the sequence is -5, -3, 1, 7

Hence, Option D is the correct answer.