Sửa lại đề: \(\left(125^3.7^4-5^9.49^2\right):2005^{2006}\)
Ta có : \(125^3.7^4=\left(5^3\right)^3.7^4=5^{3.3}.7^4=5^9.7^4\)
\(5^9.49^2=5^9.\left(7^2\right)^2=5^9.7^{2.2}=5^9.7^4\)
\(\Rightarrow125^3.7^4-5^9.49^2=5^9.7^4-5^9.7^4=0\)
mà \(2005^{2006}>0\)\(\Rightarrow\left(125^3.7^4-5^9.49^2\right):2005^{2006}=0\)