Step 1: Define the geometric mean.
The geometric mean between two numbers \( a \) and \( b \) is given by:
\[
\text{Geometric mean} = \sqrt{ab}
\]
Step 2: Set up the equation.
We are given that:
\[
\frac{a^{n+1} + b^{n+1}}{a^n + b^n} = \sqrt{ab}
\]
Now, multiply both sides by \( a^n + b^n \):
\[
a^{n+1} + b^{n+1} = \sqrt{ab} (a^n + b^n)
\]
Step 3: Solve for \( n \).
To find the value of \( n \), we solve the equation for specific values of \( a \) and \( b \). The exact solution will depend on the values of \( a \) and \( b \), but the general approach involves simplifying the equation and solving for \( n \).