Question

ex 3 dau coroana ........

Answer 1

a=2-1/3
b=2+1/3
a+b=2-1/3+2+1/3=4
a-b=2-1/3-(2+1/3)=2-1/3-2-1/3=-2/3
axb=(2-1/3)x(2+1/3)=2²-(1/3)²=4-1/9=36/9-1/9=35/9
a:b=(2-1/3):(2+1/3)=(6/3-1/3):(6/3+1/3)=5/3:7/3=5/3x3/7=5/7

Answer 2

a = 2 - $\frac{1}{3}$ (amplificam pe 2 c 3 si obtinem
a = $\frac{6-1}{3}$
a = $\frac{5}{3}$

b = 2 +  $\frac{1}{3}$  
b = $\frac{6+1}{3}$
b = $\frac{7}{3}$

a+b = $\frac{5}{3}$ + $\frac{7}{3}$
a+b = $\frac{12}{3}$
a+b = 4

b -a = $\frac{7}{3}$ - $\frac{5}{3}$
b-a = $\frac{2}{3}$

a*b = $\frac{5}{3}$ * $\frac{7}{3}$
a*b = $\frac{35}{9}$

a / b = $\frac{5}{3}$ / $\frac{7}{3}$
a / b = $\frac{5*3}{7*3}$
a / b = $\frac{15}{21}$ (simplificam fractia cu 3
a / b = $\frac{5}{7}$