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Given the first term and common ratio, find the first term and the explicit formula.

A1=1.7,r=6.0


a1=3,r=-3

A1=3.1,r=5.0

A1=5,r=4



Please help me

1 Answer

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The first terms and explicit formulas for the given geometric sequences are:

a₁ = 1.7, Explicit formula: aₙ = 1.7 *6ⁿ⁻¹

a₁ = 3, Explicit formula: aₙ = 3 * (-3)ⁿ⁻¹

a₁ = 3.1, Explicit formula: aₙ = 3.1 * 5ⁿ⁻¹

a₁ = 5, Explicit formula: aₙ = 5* 4ⁿ⁻¹

What is geometric sequence?

Given

the first term a₁

The explicit formula for a geometric sequence is given by:

aₙ = a₁ * rⁿ⁻¹

where:

aₙ is the nth term,

a₁ is the first term,

r is the common ratio, and

n is the term number.

Let's find a₁ and the explicit formula for each case:

For a₁ = 1.7 and r = 6.0

a₁ = 1.7

Explicit formula: aₙ = 1.7 *6ⁿ⁻¹

For a₁ = 3 and r = -3

a₁ = 3

Explicit formula: aₙ = 3 * (-3)ⁿ⁻¹

For a₁ = 3.1 and r = 5.0

a₁ = 3.1

Explicit formula: aₙ = 3.1 * 5ⁿ⁻¹

For a₁ = 5 and r = 4

a₁ = 5

Explicit formula: aₙ = 5* 4ⁿ⁻¹

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