... QA= {(6; 1), (5; 1), (5; 2) , (4; 1), (4; 2) , (4; 3), (3; 1), (3; 2) , (3; 3), (3; 4), (2; 1), (2; 2) , (2; 3), (2; 4), (2; 5), (1; 1), (1; 2) , (1; 3), (1; 4), (1; 5), (1; 6)} Tap Q^ cd 21 phdn tfl ... ddu hang la : 136 (a) 3! + 2! = 8; (b) 3! .2! = 12; (c)5!; (d)Ai Trd ldi Chgn (b) e) Sd each sap xdp dd hai ban nft diing kd la : (a) 3! + 2! = 8; (b) 3! .2! = 12; (c )2! x2!x3!; (d)A^ Trd ldi Chgn ... (a) 12; (b) 24 ; (e) 20 ; (d) 40 Trd ldi Chgn (b) Cdu Cho cae chft sd: 1, 3, 5, 6, So cae sd chan cd chft sd khac cd dugc tfl cac sd tren la: (a) 4.3 .2; (b) + 3+ 2; (c) 2. 4.3 .2; (d) 5.4.3 .2 Trd...