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If a(n)=(n^(2))/(3n+2), find a(1)a(5)....

If `a_(n)=(n^(2))/(3n+2)`, find `a_(1)a_(5)`.

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To solve the problem, we need to find the values of \( a_1 \) and \( a_5 \) using the given formula \( a_n = \frac{n^2}{3n + 2} \), and then calculate \( a_1 \times a_5 \). ### Step-by-Step Solution: 1. **Find \( a_1 \)**: - Substitute \( n = 1 \) into the formula: \[ a_1 = \frac{1^2}{3(1) + 2} \] - Calculate the numerator and denominator: \[ a_1 = \frac{1}{3 + 2} = \frac{1}{5} \] 2. **Find \( a_5 \)**: - Substitute \( n = 5 \) into the formula: \[ a_5 = \frac{5^2}{3(5) + 2} \] - Calculate the numerator and denominator: \[ a_5 = \frac{25}{15 + 2} = \frac{25}{17} \] 3. **Calculate \( a_1 \times a_5 \)**: - Multiply the two values obtained: \[ a_1 \times a_5 = \left(\frac{1}{5}\right) \times \left(\frac{25}{17}\right) \] - Simplify the multiplication: \[ a_1 \times a_5 = \frac{1 \times 25}{5 \times 17} = \frac{25}{85} \] - Further simplify: \[ a_1 \times a_5 = \frac{5}{17} \] ### Final Answer: \[ a_1 \times a_5 = \frac{5}{17} \]
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