a)√2-{-√3-[(√5-√2)-(√3+√7)]+(√5-√7)}=
√2-[-√3-(√5-√2-√3-√7)+√5-√7]=
√2-(-√3-√5+√2+√3+√7+√5-√7)=
√2-√2=
0
b)-1,1(6):(-1,75)+0,(3)×(-0,5)=
-1,1(6)=-1 intreg si (16-1)/90=-105/90=-7/6
-1,75=-175/100=-7/4
0,(3)=3/9=1/3
-0,5=-5/10=-1/2
-7/6:(-7/4)+1/3×(-1/2)=
-7/6×(-4/7)-1/6=
6/4-1/6=
(18-2)/12=
16/12=
4/3
