Question

Find the general term for the sequence -3, 1, 5, 9, ....

a. n - 2
b. 3n - 6
c. 4n - 7
d. -n + 4

Answer 1

C

Explanation:

The difference between that numbers is 4 so it's going to be in the 4 nth term

now 4x1 = 4

to get from 4 to -3 you need to - 7 and hence you get the nth term 4n-7

Answer 2

Answer: The correct option is (c) 4n - 7.

Step-by-step explanation: We are given to find the general term for the following sequence :

-3, 1, 5, 9, . . . .

In the sequence, we notice the following patter :

1 - (-3) = 5 - 1 = 9 - 5 = . . . =4.

So, there is a common difference of 4 between the consecutive terms and so the given sequence is an arithmetic one.

We know that

the n-th term of an arithmetic sequence with first term a and common difference d is given by

`a_n=a+(n-1)d.`

In the given sequence,

a = -3 and d = 4.

Therefore, the n-th term of the sequence will be

`a_n=-3+(n-1)*4=-3+4n-4=4n-7.`

Thus, the required general term of the sequence is (4n - 7).

Option (c) is CORRECT.