Question

Tell whether the sequence is arithmetic. If it is, what is the common difference?

19,11,3,-5

A. NO
B. Yes; 1/8
C. Yes; 8
D. Yes; -8

Answer 1

I think the answer is c

Answer 2

Answer: D. Yes ; -8

Explanation:

An arithmetic sequence is given by :-

`a_1, a_2, a_3, a_4 , ........., a_n` , where n is a natural number .

Here , differences between the successive terms is equal (d).

i.e. Common difference =
`d=a_2-a_1= a_3-a_2=a_4-a_3` and so on.

The given sequence : 19,11,3,-5

`a_2-a_1=11-19=-8`

`a_3-a_2=3-11=-8`

`a_4-a_3=-5-3=-8`

Since the differences between the successive terms are equal as -8.

So, the given sequence is an Arithmetic sequence with common difference = -8

Hence, the correct answer : Yes , given sequence is an Arithmetic ; common difference =-8