Given data:
The given expression is (5x^3 y^5) (6x^4y^3).
The given expression can be written as,
[tex]\begin{gathered} (5x^3y^5)(6x^4y^3)=(5\times6)(x^{3+4})(y^{5+3}) \\ =30x^7y^8 \end{gathered}[/tex]Thus, the given expression can be written as 30x^(7)y^(8).