a: \(x+3+\sqrt{x^2-6x+9}\)
\(=x+3+\sqrt{\left(x-3\right)^2}\)
=x+3+3-x(x<=3)
=6
b: \(\sqrt{x^2+4x+4}-\sqrt{x^2}\)
\(=\sqrt{\left(x+2\right)^2}-\left|x\right|\)
=|x+2|-|x|
=x+2-(-x)=x+2+x=2x+2
c: \(\dfrac{\sqrt{x^2-2x+1}}{x-1}=\dfrac{\sqrt{\left(x-1\right)^2}}{x-1}=\dfrac{\left|x-1\right|}{x-1}\)
\(=\dfrac{x-1}{x-1}\left(x>1\right)\)
=1
d: \(\left|x-2\right|+\dfrac{\sqrt{x^2-4x+4}}{x-2}\)
\(=2-x+\dfrac{\sqrt{\left(x-2\right)^2}}{x-2}\)
\(=2-x+\dfrac{2-x}{x-2}\)
=2-x-1
=1-x

