a) \(\left(x^2-2x+1\right):\left(x-1\right)=\left(x-1\right)^2:\left(x-1\right)=\left(x-1\right)\)
b) \(\left(x^3+1\right):\left(x^2-x+1\right)=\left(x+1\right)\left(x^2-x+1\right):\left(x^2-x+1\right)=\left(x+1\right)\)
c) \(\left(x^3-x^2-5x-3\right):\left(x-3\right)=\left(x^2-2x-3\right)\left(x+1\right)=\left(x-3\right)\left(x+1\right)^2=\left(x+1\right)^2\)

