[tex]\bf x = (2^{20})^{3} :2^{56}-2^{3}[/tex]
[tex]\bf x = 2^{20\cdot 3} :2^{56}-2^{3}[/tex]
[tex]\bf x = 2^{60} :2^{56}-2^{3}[/tex]
[tex]\bf x = 2^{60-56} -2^{3}[/tex]
[tex]\bf x = 2^{4} -2^{3}[/tex]
[tex]\bf x = 2^{3} \cdot(2^{4-3} -2^{3-3})[/tex]
[tex]\bf x = 2^{3} \cdot(2^{1} -2^{0})[/tex]
[tex]\bf x = 2^{3} \cdot(2 -1)[/tex]
[tex]\bf x = 2^{3} \cdot 1[/tex]
[tex]\boxed{\bf x = 2^{3} = 8}[/tex]
[tex]\bf y = (3^{23}-3^{22}-3^{21}-3^{20}) :3^{20}+3^{0}+3^{1}[/tex]
[tex]\bf y = 3^{20}\cdot(3^{23-20}-3^{22-20}-3^{21-20}-3^{20-20}) :3^{20}+1+3[/tex]
[tex]\bf y = 3^{20}\cdot(3^{3}-3^{2}-3^{1}-3^{0}) :3^{20}+4[/tex]
[tex]\bf y = 3^{20}\cdot(27-9-3-1) :3^{20}+4[/tex]
[tex]\bf y = 3^{20}\cdot 14 :3^{20}+4[/tex]
[tex]\bf y = 3^{20-20}\cdot 14 +4[/tex]
[tex]\bf y = 3^{0}\cdot 14 +4[/tex]
[tex]\bf y = 1\cdot 14 +4[/tex]
[tex]\boxed{\bf y = 18}[/tex]
