a) (25x^5 – 5x^4 + 10x^2) : 5x^2
= (25x^5 : 5x^2) – (5x^4 : 5x^2) + (10x^2 : 5x^2)
= 5x^3 – x^2 + 2
b) (15x^3y^2- 6x^2y – 3x^2y^2) : 6x^2y
= (15x^3y^2 : 6x^2y) + (-6x^2y : 6x^2y) + (- 3x^2y^2 : 6x^2y)
=\(\frac{15}{6}xy-1-\frac{3}{6}y\)
=\(\frac{5}{2}xy-1-\frac{1}{2}y\)