Đáp án:(x;y)=(2;31); (0;-33); (34;-33); (-32;31); (4;7); (-2;-9); (11;-8); (-10;7)
Giải thích các bước giải:
(x-1)(x+y)=33
⇒x-1; x+y∈U(33)
⇒x-1; x+y∈U(33)={-1;1;-33;33;-11;11;-3;3}
⇒(1)$\left \{ {{x-1=1} \atop {x+y=33}} \right.$ ⇔$\left \{ {{x=2} \atop {y=31}} \right.$
⇒(2)$\left \{ {{x-1=-1} \atop {x+y=-33}} \right.$ ⇔$\left \{ {{x=0} \atop {y=-33}} \right.$
⇒(3)$\left \{ {{x-1=33} \atop {x+y=1}} \right.$ ⇔$\left \{ {{x=34} \atop {y=-33}} \right.$
⇒(4)$\left \{ {{x-1=-33} \atop {x+y=-1}} \right.$ ⇔$\left \{ {{x=-32} \atop {y=31}} \right.$
⇒(5)$\left \{ {{x-1=3} \atop {x+y=11}} \right.$ ⇔$\left \{ {{x=4} \atop {y=7}} \right.$
⇒(6)$\left \{ {{x-1=-3} \atop {x+y=-11}} \right.$ ⇔$\left \{ {{x=-2} \atop {y=-9}} \right.$
⇒(7)$\left \{ {{x-1=11} \atop {x+y=3}} \right.$ ⇔$\left \{ {{x=11} \atop {y=-8}} \right.$
⇒(8)$\left \{ {{x-1=-11} \atop {x+y=-3}} \right.$ ⇔$\left \{ {{x=-10} \atop {y=7}} \right.$
⇒(x;y)=(2;31); (0;-33); (34;-33); (-32;31); (4;7); (-2;-9); (11;-8); (-10;7)
