MATH SOLVE

3 months ago

Q:
# which formula can be used to describe the sequence? 1.2, 3, 7.5, 18, 7.5, ...

Accepted Solution

A:

The given sequence is 1.2, 3, 7.5, 18.75, ...,

This is a geometric sequence with common ratio of 2.5, because

3/1.2 = 2.5

7.5/3 = 2.5

18.75/7.5 = 2.5

The 1st term is a₁ = 1.2(2.5)⁰

The 2nd term is a₂ = 1.2(2.5)¹

The 3rd term is a₃ = 1.2(2.5)²

and so on

Therefore the sequence obeys the formula

f(x) = 1.2(2.5)ˣ⁻¹

Answer: [tex]f(x) = 1.2(2.5)^{x-1}[/tex]

This is a geometric sequence with common ratio of 2.5, because

3/1.2 = 2.5

7.5/3 = 2.5

18.75/7.5 = 2.5

The 1st term is a₁ = 1.2(2.5)⁰

The 2nd term is a₂ = 1.2(2.5)¹

The 3rd term is a₃ = 1.2(2.5)²

and so on

Therefore the sequence obeys the formula

f(x) = 1.2(2.5)ˣ⁻¹

Answer: [tex]f(x) = 1.2(2.5)^{x-1}[/tex]