6. \((d^5)^2\cdot(d^3)^3\)

\((d^5)^2=d^{10}\), \((d^3)^3=d^9\).

\((d^5)^2\cdot(d^3)^3=d^{10}\cdot d^9=d^{10+9}=d^{19}\).

Ответ: \(d^{19}\)