\(11^6-11^5+11^4\)
\(=11^4.11^2-11^4.11+11^4.1\)
\(=11^4.121-11^4.11+11^4.1\)
\(=11^4\left(121-11+1\right)\)
\(=11^4.111⋮111\rightarrowđpcm\)
\(16^5+2^{19}-8^6\)
\(=\left(2^4\right)^5+2^{19}-\left(2^3\right)^6\)
\(=2^{20}+2^{19}-2^{18}\)
\(=2^{18}.2^2+2^{18}.2-2^{18}.1\)
\(=2^{18}.4+2^{18}.2-2^{18}.1\)
\(=2^{18}\left(4+2-1\right)\)
\(=2^{18}.5\)
\(=2^{17}.10⋮10\rightarrowđpcm\)