Tìm x ϵ Z biết :
a, 4 ⋮ x + 1
b , x + 5 ⋮ x +2
c , x - 7 ⋮ x - 2
d , 2x + 5 ⋮ x + 1
e , 3x - 1 ⋮ x + 2
a) x+1\(\in\)Ư(4)=\(\left\{\pm1;\pm2;\pm4\right\}\)
x+1 | 1 | -1 | 2 | -2 | 4 | -4 |
x | 0 | -2 | 1 | -3 | 3 | -5 |
b)(x+2)+3\(⋮\)x+2
3\(⋮\)x+2
x+2\(\in\)Ư(3)=\(\left\{\pm1;\pm3\right\}\)
x+2 | 1 | -1 | 3 | -3 |
x | -1 | -3 | 1 | -5 |
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