1:
a: =>6a-2+3 chia hết cho 3a-1
=>\(3a-1\in\left\{1;-1;3;-3\right\}\)
mà a nguyên
nên a=0
b: \(\Leftrightarrow6a+10⋮2a-1\)
=>6a-3+13 chia hết cho 2a-1
=>\(2a-1\in\left\{1;-1;13;-13\right\}\)
=>\(a\in\left\{1;0;7;-6\right\}\)
c: \(\Leftrightarrow a^2-2a-3a+6-6⋮a-2\)
=>\(a-2\in\left\{1;-1;2;-2;3;-3;6;-6\right\}\)
=>\(a\in\left\{3;1;4;0;5;-1;8;-4\right\}\)
d: \(\Leftrightarrow6a-3-1⋮2a-1\)
=>\(2a-1\in\left\{1;-1\right\}\)
=>\(a\in\left\{1;0\right\}\)
e: \(\Leftrightarrow6a-9⋮3a+1\)
=>\(6a+2-11⋮3a+1\)
=>\(3a+1\in\left\{1;-1;11;-11\right\}\)
=>\(a\in\left\{0;-4\right\}\)