What are the first three terms of a geometric sequence in which the first term is 4 common ratio is 5?

Solution:

Given:

first term (a) = 4

common ratio (r) = 5

The formula for the n^th term for a geometric sequence is given as,

a_n = a.r^n-1

where,

first term = (a)

common ratio = (r)

Now, put the values in geometric sequence formula,

a₁ = 4.5^1-1 = 4.1 = 4

a₂ = 4.5^2-1 = 4.5 = 20

a₃ = 4.5^3-1 = 4.25 = 100

Therefore, the first three terms are 4, 20, 100

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What are the first three terms of a geometric sequence in which the first term is 4 common ratio is 5?

Summary:

The first three terms of a geometric sequence in which the first term is 4 common ratio is 5 are 4, 20 and 100.