tentukan nilai n^2 - 1 jika 4! nC4 = 5 nP3!
Matematika
yousrilanka
Pertanyaan
tentukan nilai n^2 - 1 jika 4! nC4 = 5 nP3!
1 Jawaban
-
1. Jawaban arsetpopeye
4! . nC4 = 5 . nP3
4! . n!/(n - 4)!.4! = 5 . n!/(n - 3)!
n! / (n - 4)! = 5 . n! / (n - 3)(n - 4)! ====> n! dan (n - 4)! Coret
1/1 = 5/(n - 3)
n - 3 = 5
n = 8
n^2 - 1 = 8^2 - 1 = 64 - 1 = 63