\(2,Ư\left(8\right)=\left\{-8;-4;-2;-1;1;2;4;8\right\}\\ Ư\left(11\right)=\left\{-11;-1;1;11\right\}\\ Ư\left(19\right)=\left\{-19;-1;1;19\right\}\\ Ư\left(28\right)=\left\{-28;-14;-7;-4;-2;-1;1;2;4;7;14;28\right\}\)
3.
\(A,45=3^2\cdot5\) nên có \(\left(2+1\right)\left(1+1\right)=6\left(ước\right)\)
\(B,103=103\) nên có \(1+1=2\left(ước\right)\)
2. Ư(8) = {1; 2; 4; 8}
Ư(11) = {1; 11}
Ư(19) = {1; 19}
Ư(28) = {1; 2; 4; 7; 14; 28}
3. Ư(45) = {1; 3; 5; 9; 15; 45} \(\Rightarrow\) 45 có 6 ước
Ư(103) = {1; 103} \(\Rightarrow\) 103 có 2 ước