a) 18^8x9^4=(2x3^2)^8x(3^2)^4=2^8.3^16.3^8=2^8.3^24
b) 4^14x5^28=4^14x25^14=100^14
c) 12^nx2^2n=(2^2x3)^nx2^2n=2^2nx3^nx2^2n=2^4nx3^n
học tốt
\(18^8\cdot9^4=18^8\cdot\left(3^2\right)^4=18^8\cdot3^8=\left(18.3\right)^8=54^8\)
\(4^{14}\cdot5^{28}=\left(2^2\right)^{14}\cdot5^{28}=2^{28}\cdot5^{28}=\left(2\cdot5\right)^{28}=10^{28}\)
\(12^n\cdot2^{2n}=12^n\cdot4^n=\left(12\cdot4\right)^n=48^n\)