Question

the first 4 terms in of the sequence
an=(-1)n-1 ×2n+1given by​

Answer 1

Answer:

hope it helps

Step-by-step explanation:

We have, a  

n

​  

=(−1)  

n−1

.2  

n

 

Putting n=1,2,3,4 and 5, we get

a  

1

​  

=(−1)  

1−1

×2  

1

=(−1)  

0

×2=2

a  

2

​  

=(−1)  

2−1

×2  

2

=(−1)  

1

×4=−4

a  

3

​  

=(−1)  

3−1

×2  

3

=(−1)  

2

×8=8

a  

4

​  

=(−1)  

4−1

×2  

4

=(−1)  

3

×16=−16

and, a  

5

​  

=(−1)  

5−1

×2  

5

=(−1)  

4

×32=32

The first five terms are 2,−4,8,−16,32