a) \(8x^3-\dfrac{1}{27}=\left(2x-\dfrac{1}{3}\right)\left(4x^2+\dfrac{2}{3}x+\dfrac{1}{9}\right)\)
b) \(\dfrac{1}{8}a^3-125b^6=\left(\dfrac{1}{2}a-5b^2\right)\left(\dfrac{1}{4}a+\dfrac{5}{2}ab^2+25b^4\right)\)
c) \(125+\left(a-b\right)^3=\left(5+a-b\right)\left(25-5a+5b+a^2-2ab+b^2\right)\)