\(\dfrac{5.4^6.9^5+6^{10}.10^2}{8^4.3^{12}-6^{11}}=\dfrac{5.\left(2^2\right)^6.\left(3^2\right)^5+\left(2.3\right)^{10}.\left(5.2\right)^2}{\left(2^3\right)^4.3^{12}-\left(2.3\right)^{11}}\)
=\(\dfrac{5.2^{12}.3^{10}+2^{10}.3^{10}.5^2.2^2}{2^{12}.3^{12}-2^{11}.3^{11}}=\dfrac{5.2^{12}.3^{10}\left(1+5\right)}{2^{11}.3^{11}\left(2.3-1\right)}\)
=\(\dfrac{5.2.6}{1.3.5}=4\)