Question

Paul a inventat o operatie algebrica, notata □ si definita prin a□b este media artimetica a numerelor reale a si b. a) calculeaza 2□4 si (-1)□5 , b) rezolva in R ecuatia x□3=1,5 , c)verifica daca noua operatie algebrica,inventata de Paul este asociativa.

Answer 1

2 patratel 4=3
-1 patratel5=4/2=2

xpatratel3=1,5
x+3=5*2
x=7

(a patratel b)patreatel c=[(a+b)/2] patratel c= a/4+b/4+c/2

apatratel (bpatratelc)= apatratel (b+c)/2= a/2+b/4+c/4≠a/4+b/4+c/2
nu e asociativa
 as simple as that!