For which values of x does the series x * 3^n / (2^n) converge?

To determine for which values of x the series Σ (x * (3^n) / (2^n)) converges, we can rewrite the expression inside the summation.

The series can be expressed as:

Σ (x * (3^n) / (2^n)) = x * Σ (3/2)^n

Now, we analyze the series Σ (3/2)^n.

This is a geometric series with a common ratio of r = 3/2. A geometric series converges if the absolute value of the common ratio is less than 1:

|r| < 1

In our case:

|3/2| = 1.5 > 1

This tells us that the series Σ (3/2)^n diverges.

However, if we want the entire series Σ (x * (3/2)^n) to converge, we must explore the behavior of the series as a whole. Since the geometric series diverges, it means that:

x must be equal to 0 for the entire series to converge. If x = 0, the terms of the series become:

Σ 0 = 0, which converges.

Thus, the only value of x for which the series converges is:

x = 0

In conclusion, the series x * (3^n) / (2^n) converges only when x = 0.

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