\(\dfrac{2}{36a^2b^2-1};\dfrac{1}{6ab+1^2};\dfrac{1}{6ab-1^2}\)

\(\dfrac{x}{x^3-27};\dfrac{2x}{x^2-6x+9};\dfrac{1}{x^2+3x+9x}\)

\(\dfrac{x^2-x}{x^2-1};\dfrac{3x}{x^3+2x^2+x};2x\)

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