Evaluate \(^{n^2 + 1}\)C\(_{n+5}\) if n = 3
- 55
-
45
- 35
- 25
The correct answer is: B
Explanation
\(^{3^2 + 1}\)C\(_{3+5}\)
\(^{9 + 1}\)C\(_{3+5}\)
\(^{10}\)C\(_{8}\) = \(\frac{10!}{8! 2!}\)
\(\frac{10 * 9 * 8!}{8! 2!}\) = \(\frac{10 * 9}{2}\)
= 45
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