Question

Ma ajuta cineva macar ex.2si4 multumesc

Answer 1

2 a ) P7/P5=7!/5!= 5! * 6*7/5!=6*7=42


2b)  3!+ 5!/3!+6=6+4*5+6=12+20=32
Am tinut cont ca Cde 4 luate cate 2 =6
2c) dupa simplificari, ramane(n-1)*n


4) a0)
4 5n+n=24
6n=24
n=4

b) CE n≥3

n/ (n-3)!=5(n-1)(n-2)
(n-2)(n-1)n=5(n-1)(n-2)
(n-2)(n-1)n-5(n-1)(n-2) =0
(n-2)(n-1)(n-5)=0 cum n≥3 convine doar n=5