Question

Thực hiện phép tính

a, \(9^8:\left(27^3.81^2\right)\)

b,\(\left(125^4.7^{10}\right):\left(5^{12}.343^3\right)\)

Answer 1

a) \(9^8=\left(3^2\right)^8=3^{16}\)

\(27^3=\left(3^3\right)^3=3^9\)

\(81^2=\left(3^4\right)^2=3^8\)

\(\Leftrightarrow3^{16}:\left(3^9.3^8\right)\)

\(\Leftrightarrow3^{16}:3^{17}\)

\(\Leftrightarrow3^{-1}=\frac{1}{3}\)

Answer 2

a) 9^́́́8 : ̣(27³ . 81²)= 3^{16  :} 3⁹ . 3⁸ = 3¹⁵

Answer 3

b) \(125^4=\left(5^3\right)^4=5^{12}\)

\(343^3=\left(7^3\right)^3=7^9\)

\(=\frac{5^{12}.7^{10}}{5^{12}.7^9}\)

\(=\frac{7^{10}}{7^9}\)

\(=7\)