Question

a) Daca a•b=3 supra 4 si c= 8 supra 9 , calculati a•(b•c); b) Daca a•b=12 supra 13 si c= 26 supra 15, calculati (a•b)•c; c) Daca a= 72 supra 25 si b•c= 35 supra 18, calculati (a•b)•c.

Answer 1

a)
axb=3/4
c=8/9
ax(bxc)=axbxc=3/4x8/9=2/3

b)
axb=12/13
c=26/15
(axb)xc=12/13x26/15=8/5

c)
a=72/25
bxc=35/18
(axb)x3=axbxc=72/25x35/18=28/5