\(a)\) Ta có: \(120=12.10=(3.4).(2.5)\)\(=(3.2.2).(2.5)=2^3.3.5\).
Vậy \(120 = {2^3}.3.5\)
\(b)\) Ta có: \(900=9.100=(3.3).(10.10)\)\(=(3.3).(2.5.2.5)=2^2.3^2.5^2\).
Vậy \(900 = {2^2}{.3^2}{.5^2}\)
\(c)\) Ta có: \(100000=10.10.10.10.10\)\(=(2.5).(2.5).(2.5).(2.5).(2.5)\)\(=2^5.5^5\).
Vậy \(100000 = {2^5}{.5^5}\)