484. 1) aᵐ⁺¹: aᵐ; 2) cⁿ⁺¹: cⁿ; 3) xⁿ⁺¹: xⁿ⁻¹; 4) yⁿ⁺¹: yⁿ⁻¹.

Решение:

1. \( \frac{a^{m+1}}{a^m} = a^{(m+1)-m} = a^1 = a \)
2. \( \frac{c^{n+1}}{c^n} = c^{(n+1)-n} = c^1 = c \)
3. \( \frac{x^{n+1}}{x^{n-1}} = x^{(n+1)-(n-1)} = x^{n+1-n+1} = x^2 \)
4. \( \frac{y^{n+1}}{y^{n-1}} = y^{(n+1)-(n-1)} = y^{n+1-n+1} = y^2 \)

Ответ: 1) a; 2) c; 3) x²; 4) y².