Решите уравнение: ((x^7 )^2·(x^3 )^4)/((x^4 )^5·x^5 )=21.

\[\frac{\left( x^{7} \right)^{2} \cdot \left( x^{3} \right)^{4}}{\left( x^{4} \right)^{5} \cdot x^{5}} = 21\]

\[\frac{x^{14} \cdot x^{12}}{x^{20} \cdot x^{5}} = 21\]

\[\frac{x^{26}}{x^{25}} = 21\]

\[x = 21.\]