Middle term property (geometric)

a_n^2=a_{n-1}\cdot a_{n+1}

Result unit: — (liczba)

What it describes

The square of a term of a geometric sequence equals the product of its neighbors.

a_n

middle term

a_{n-1}, a_{n+1}

neighboring terms

In a geometric sequence the square of a term equals the product of its neighbors — the middle term is the geometric mean of the neighbors.

Checking whether a sequence is geometric; three consecutive terms.

The neighboring terms are 4 and 9. Compute the middle term (positive).

Substitution

a^2=4\cdot9=36

Result

a=\sqrt{36}=6

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