Question

Find the geometric sequence with a1=-3 and r=-2,find a5

Answer 1

The equation would be:

-3(-2) ^n-1

-3, 6,-12, 24, 48

so a5=48

Answer 2

the
`a_5 =-48`

Explanation:

• Geometric sequence is written as: a, ar, ar², ar³,.... where r is common ratio.

• The general term of geometric sequence is written as
  `a_n =a_1 r^(n-1)`

in this question, we need to find the 5th term of geometric sequence

so, we will put n=5,r=-2 and
`a_n =-3}` in
`a_n =a_1 r^(n-1)`;

`a_5 =(-3) (-2)^(5-1)`

`a_5 =(-3) (-2)^(4)`

`a_5 =(-3) (16)`

`a_5 =-48`

Therefore, the
`a_5 =-48`