\(b,81^{13}:3^{35}.\)
\(=\left(3^4\right)^{13}:\left(3^1\right)^{35}.\)
\(=3^{52}:3^{35}.\)
\(=3^{52-35}=3^{17}.\)
Vậy.....
\(c,128^{18}:32^{23}.\)
\(=\left(2^7\right)^{18}:\left(2^5\right)^{23}.\)
\(=2^{126}:2^{115}.\)
\(=2^{126-115}.\)
\(=2^{11}=2048.\)
Vậy.....
~ Hok tốt!!! ~ =))