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Expansion of Binomial Coefficients

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Given that the coefficient of x3x^3 is 3 times that of x2x^2 in the expansion (2+3x)n(2 + 3x)^n, find the value of nn.

This problem focuses on binomial expansions and the use of binomial coefficients. When exploring binomial expansions, it's crucial to understand how the coefficients are derived and how the powers of different terms come together in the expression. In the expansion of a binomial expression like (2+3x)n(2 + 3x)^n, each term can be expressed using the binomial theorem, which relies on binomial coefficients. The binomial coefficient, denoted as C(n,k)C(n, k), is used to find the coefficients of xx in each term of the expansion.

In this problem, you're asked to compare coefficients of different powers of xx, specifically x3x^3 and x2x^2. Understanding how to work with coefficients involves recognizing patterns and knowing how they relate to each other in various powers. A key strategy here is using relationships between coefficients to set up a system of equations that can be solved for nn, effectively applying algebraic manipulation and reasoning. Combinatorial reasoning can sometimes come into play, especially when identifying how different terms, once expanded, contribute to the coefficient of a specific power. Exploring this problem offers insight into how binomial expansions are not only about algebraic techniques but also numerical reasoning and combinatorial logic.

Posted by Gregory 13 hours ago

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