Question

Tính tích: \(9{{\rm{x}}^5}{y^4}.2{{\rm{x}}^4}{y^2}\).

Answer 1

Ta có: \(9{{\rm{x}}^5}{y^4}.2{{\rm{x}}^4}{y^2} = \left( {9.2} \right).\left( {{x^5}.{x^4}} \right).\left( {{y^4}.{y^2}} \right) = 18{{\rm{x}}^9}{y^6}\)