\(a.\sqrt{4x^2-4x+1}=3\)
⇔ \(\sqrt{\left(2x-1\right)^2}=3\)
⇔ \(\text{ |}2x-1\text{ |}=3\)
⇔ \(2x-1=3or2x-1=-3\)
⇔ \(x=2orx=-1\)
\(b.3\left(\sqrt{x}+2\right)+5=4\sqrt{4x}+1\) ( x ≥ 0 )
⇔ \(3\sqrt{x}+11=8\sqrt{x}+1\)
⇔ \(x=4\left(TM\right)\)
KL.........