Câu 32: B

Câu 33: C

a)\(x^2-x+\dfrac{1}{4}\)

\(\Leftrightarrow\left(x-\dfrac{1}{2}\right)^2=0\Leftrightarrow x=\dfrac{1}{2}\)

a)\(6x^2-3xy=3x\left(2x-y\right)\)

b)\(x^2-y^2-6x+9=\left(x-3\right)^2-y^2\)

                               \(=\left(x-3-y\right)\left(x-3+y\right)\)

c)\(x^2+5x-6=x^2-x+6x-6\)

                       \(=\left(x-1\right)\left(x-6\right)\)