Question

Find the fifth term of an=2(-1) n

Answer 1

The fifth term of
`a_n = 2(-1)^n` is, -2

Explanation:

Given the sequence:

`a_n = 2(-1)^n` .....[1]

where,

n is the number of terms.

To find the fifth term of the given sequence:

Substitute n = 5 in [1] we have;

`a_5 = 2 \cdot (-1)^5`

⇒
`a_5 = 2 \cdot -1 = -2`

Therefore, the value of fifth term of
`a_n` is, -2

Answer 2

The 5th answer in this series would be -2.

We know this because in any problem where we have a base (2) being multiplied by a -1^n power, the numbers will simply alternate between positive 2 and negative 2. All of the even powers will be positive 2 and all of the odd numbers will be negative 2. See the work below.

2(-1)(-1)(-1)(-1)(-1)
2 (1)(-1)(-1)(-1)
2(1)(1)(-1)
2(-1)
-2

So since 5 is odd, the answer is negative 2.