Answer :

To determine the coefficient of the [tex]\( x^5 \)[/tex] term in the expansion of [tex]\( (2x + 3)^7 \)[/tex], we can use the binomial theorem. The binomial theorem states that:

[tex]\[ (a + b)^n = \sum_{k=0}^{n} \binom{n}{k} a^{n-k} b^k \][/tex]

In this case, the expression is [tex]\( (2x + 3)^7 \)[/tex]. Here, [tex]\( a = 3 \)[/tex], [tex]\( b = 2x \)[/tex], and [tex]\( n = 7 \)[/tex].

We are interested in the coefficient of the [tex]\( x^5 \)[/tex] term. This term corresponds to [tex]\( b^5 \)[/tex], so we will use [tex]\( b = 2x \)[/tex] in our calculations.

1. Identify the appropriate term:
[tex]\[ T(k) = \binom{n}{k} a^{n-k} b^k \][/tex]
For the [tex]\( x^5 \)[/tex] term, [tex]\( k = 5 \)[/tex].

2. Calculate each component:

- Binomial coefficient [tex]\( \binom{7}{5} \)[/tex]:
[tex]\[ \binom{7}{5} = 21 \][/tex]

- Calculate [tex]\( a^{n-k} \)[/tex], where [tex]\( a = 3 \)[/tex] and [tex]\( n - k = 2 \)[/tex]:
[tex]\[ 3^{2} = 9 \][/tex]

- Calculate [tex]\( b^k \)[/tex], where [tex]\( b = 2x \)[/tex] and [tex]\( k = 5 \)[/tex]:
[tex]\[ (2x)^5 = 2^5 \cdot x^5 = 32 x^5 \][/tex]

3. Combine these elements to form the term [tex]\( T(5) \)[/tex]:
[tex]\[ T(5) = \binom{7}{5} \cdot 3^2 \cdot 32 x^5 \][/tex]

4. Evaluate the coefficient:
[tex]\[ T(5) = 21 \cdot 9 \cdot 32 x^5 \][/tex]
[tex]\[ T(5) = 6048 x^5 \][/tex]

Thus, the coefficient of the [tex]\( x^5 \)[/tex] term in the expansion of [tex]\( (2x + 3)^7 \)[/tex] is:

[tex]\[ \boxed{6048} \][/tex]

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