Question

Tolong jawab soal no 3 yang B

Answer 1

(n + 3)C4 = 2 . (n + 2)C3
=> (n + 3)! / (n + 3 - 4)!.4! = 2 . (n + 2)!/(n + 2 - 3)!.3!
=> (n + 3)(n + 2)! / (n - 1)! . 4 . 3! = 2 . (n + 2)!/(n - 1)!.3!
=> (n + 3)/4 = 2
=> n + 3 = 8
=> n = 5