Bài 2: Theo đầu bài ta có:
a) \(137^{15}\)
\(=\left(137^4\right)^3\cdot137^3\)
\(=\left(...1\right)^3\cdot\left(...3\right)\)
\(=\left(...1\right)\cdot\left(...3\right)\)
\(=\left(...3\right)\)
b) \(234^{44}\)
\(=\left(234^2\right)^{22}\)
\(=\left(...6\right)^{22}\)
\(=\left(...6\right)\)
Bài 1: Theo đầu bài ta có:
1) \(3^{20}:3^{15}\cdot2^7:2^6:3^3\)
\(=\left(3^{20}:3^{15}:3^3\right)\cdot\left(2^7:2^6\right)\)
\(=3^2\cdot2^1\)
\(=9\cdot2\)
\(=18\)
2) \(4^2\cdot3^5:12^2:3^3\)
\(=\left(4^2:12^2\right)\cdot\left(3^5:3^3\right)\)
\(=\left(\frac{4}{12}\right)^2\cdot3^2\)
\(=\left(\frac{1}{3}\cdot3\right)^2\)
\(=1^2\)
\(=1\)