Решение:
- \(\frac{a^4}{a^6} = \frac{1}{a^2}\)
- \(\frac{x^8}{x^6} = x^2\)
- \(\frac{mn}{m^3} = \frac{n}{m^2}\)
- \(\frac{4a^2b^3}{6ab} = \frac{2ab^2}{3}\)
- \(\frac{cd^2}{c^3} = \frac{d^2}{c^2}\)
- \(\frac{15x^2y^6}{20x^4y^5} = \frac{3y}{4x^2}\)
Ответ: \(\frac{1}{a^2}\), \(x^2\), \(\frac{n}{m^2}\), \(\frac{2ab^2}{3}\), \(\frac{d^2}{c^2}\), \(\frac{3y}{4x^2}\).