\(2\left(a-1\right)x-a\left(x-1\right)=2a+3\\ \Leftrightarrow2ax-2x-ax+a=2a+3\\ \Leftrightarrow-2x=-ax+a+3\\ \Leftrightarrow-2x=-2x-2+3\\ \Leftrightarrow0x=-1\Leftrightarrow x\in\varnothing\)
\(2\left(a-1\right)x-a\left(x-1\right)=2a+3\)
\(\Leftrightarrow2ax-2x-ax+a=2a+3\)
\(\Leftrightarrow2x-ax+a+3=0\)
\(\Leftrightarrow2x-2x+2+3=0\)
\(\Leftrightarrow5=0\left(VLý\right)\)
Vậy \(S=\varnothing\)
Thay a=2 vào biểu thức trên ta có:
\(2\left(a-1\right)x-a\left(x-1\right)=2a+3\)
\(2\left(2-1\right)x-2\left(x-1\right)=2.2+3\)
\(2x-2x+2=7\)
\(2=7\)(Vô lí)
