Question

Please help me, PLEASE!!!!!!

Tell wheather the sequence is arithmetic. If it is , what is the common difference? -12,-7,-2,3.......

A yes ;5
B yes ;8
C yes :3
D no

Answer 1

C

Explanation:

To find whether it is a arithmetic or geometric sequence it is easiest to try to subtract term a2 from a1, seeing if d or r is positive. If that does not heed an answer try dividing a2 by a1 to see if it is a geometric sequence.

The terms go as follows just in case (They would normally be in subscripts)-

a1= -12

a2= -7

a3= -2

a4= 3

Answer 2

Answer: Yes; 5 (choice A)

We add 5 to each term to get the next

-12+5 = -7

-7+5 = -2

-2+5 = 3

and so on. The nth term formula is

an = -12 + 5(n-1)

If you were to plug in n = 1, 2, 3, ... then it should generate the terms shown