[tex]\begin{gathered} 2\sqrt[]{25y^8}\cdot4\sqrt[]{6y^3}= \\ 8\sqrt[]{25y^8}\cdot\sqrt[]{6y^3}= \\ 8\sqrt[]{25}\cdot\sqrt[]{y^8}\cdot\sqrt[]{6y^3}= \\ 8\cdot5\cdot y^4\cdot\sqrt[]{6y^3}= \\ 40\cdot y^4\cdot\sqrt[]{6y^3}= \\ 40\cdot y^4\cdot\sqrt[]{6y^{}\cdot y^2}= \\ 40\cdot y^4\cdot\sqrt[]{6y^{}}\cdot y= \\ 40\cdot y^5\cdot\sqrt[]{6y^{}}\cdot \end{gathered}[/tex][tex]\begin{gathered} \\ \\ \\ \sqrt[]{y^8}=y^{\frac{8}{2}}=y^4 \end{gathered}[/tex]
