Решение:
Для решения будем использовать свойства степеней: \( a^m \cdot a^n = a^{m+n} \) и \( \frac{a^m}{a^n} = a^{m-n} \), а также \( (a^m)^n = a^{m \cdot n} \).
- \( \frac{a^9 \cdot a^{12}}{a^{18}} = \frac{a^{9+12}}{a^{18}} = \frac{a^{21}}{a^{18}} = a^{21-18} = a^3 \). При \( a=4 \): \( 4^3 = 64 \).
- \( \frac{a^{12} \cdot a^6}{a^{14}} = \frac{a^{12+6}}{a^{14}} = \frac{a^{18}}{a^{14}} = a^{18-14} = a^4 \). При \( a=3 \): \( 3^4 = 81 \).
- \( \frac{a^{11} \cdot a^9}{a^{18}} = \frac{a^{11+9}}{a^{18}} = \frac{a^{20}}{a^{18}} = a^{20-18} = a^2 \). При \( a=7 \): \( 7^2 = 49 \).
- \( \frac{a^9 \cdot a^8}{a^{12}} = \frac{a^{9+8}}{a^{12}} = \frac{a^{17}}{a^{12}} = a^{17-12} = a^5 \). При \( a=2 \): \( 2^5 = 32 \).
- \( \frac{a^{16} \cdot a^{-7}}{a^8} = \frac{a^{16-7}}{a^8} = \frac{a^9}{a^8} = a^{9-8} = a^1 = a \). При \( a=3 \): \( 3 \).
- \( \frac{a^{18} \cdot a^{-6}}{a^{10}} = \frac{a^{18-6}}{a^{10}} = \frac{a^{12}}{a^{10}} = a^{12-10} = a^2 \). При \( a=5 \): \( 5^2 = 25 \).
- \( \frac{a^{17} \cdot a^{-6}}{a^9} = \frac{a^{17-6}}{a^9} = \frac{a^{11}}{a^9} = a^{11-9} = a^2 \). При \( a=4 \): \( 4^2 = 16 \).
- \( \frac{a^{19} \cdot a^{-11}}{a^5} = \frac{a^{19-11}}{a^5} = \frac{a^8}{a^5} = a^{8-5} = a^3 \). При \( a=5 \): \( 5^3 = 125 \).
- \( \frac{(a^4)^5}{a^{18}} = \frac{a^{4 \cdot 5}}{a^{18}} = \frac{a^{20}}{a^{18}} = a^{20-18} = a^2 \). При \( a=6 \): \( 6^2 = 36 \).
- \( \frac{(a^8)^2}{a^{11}} = \frac{a^{8 \cdot 2}}{a^{11}} = \frac{a^{16}}{a^{11}} = a^{16-11} = a^5 \). При \( a=2 \): \( 2^5 = 32 \).
- \( \frac{(a^8)^2}{a^{13}} = \frac{a^{8 \cdot 2}}{a^{13}} = \frac{a^{16}}{a^{13}} = a^{16-13} = a^3 \). При \( a=5 \): \( 5^3 = 125 \).
- \( \frac{(a^3)^5}{a^{11}} = \frac{a^{3 \cdot 5}}{a^{11}} = \frac{a^{15}}{a^{11}} = a^{15-11} = a^4 \). При \( a=3 \): \( 3^4 = 81 \).
Ответ: 1. 64; 2. 81; 3. 49; 4. 32; 5. 3; 6. 25; 7. 16; 8. 125; 9. 36; 10. 32; 11. 125; 12. 81.