We are given the following expression:
![\log \frac{\sqrt[3]{b^2c^4}}{a^8}](https://img.qammunity.org/2023/formulas/mathematics/college/iw9tjretq4an97l37jbh4zqryc0km5ll1q.png)
To determine the numerical value of the expression we will use different "log" properties to expand it.
First, we will use the following property:
![\log (x)/(y)=\log x-\log y](https://img.qammunity.org/2023/formulas/mathematics/college/f9plovotsc6pghxreztqcnool2ohcwc2ry.png)
Applying the property we get:
![\log \frac{\sqrt[3]{b^2c^4}}{a^8}=\log \sqrt[3]{b^2c^4}-\log a^8](https://img.qammunity.org/2023/formulas/mathematics/college/k4v21i8i3g1colsnlfrgrl5f1a6r8ewuh2.png)
Now, we will use the following property of roots:
![\sqrt[n]{x}=x^{(1)/(n)}](https://img.qammunity.org/2023/formulas/mathematics/high-school/2lu2vv6gbt2u5kod14f6c6vnozt0gooe6m.png)
Applying the property we get:
![\log \sqrt[3]{b^2c^4}-\log a^8=\log (b^2c^4)^{(1)/(3)}-\log a^8](https://img.qammunity.org/2023/formulas/mathematics/college/dpe2f13v2sao8kdd78nvabs7483cg1tgyp.png)
Now, we use the following property:
![\log x^n=n\log x](https://img.qammunity.org/2023/formulas/mathematics/college/ddcyz8rd4bgprewimd0igpkizay5tk1pr2.png)
Applying the property:
![\log (b^2c^4)^{(1)/(3)}-\log a^8=(1)/(3)\log b^2c^4-8\log a](https://img.qammunity.org/2023/formulas/mathematics/college/8dabmymtj8g8qonrn8uneik5fv2eojq4yc.png)
Now, we apply the following property on the "log" on the left side:
![(1)/(3)\log b^2c^4-8\log a=(1)/(3)\log (b^2)+(1)/(3)\log c^4-8\log a](https://img.qammunity.org/2023/formulas/mathematics/college/4y0zz44k8x9l0r6crebi202jrecpkjlagn.png)
Now, we apply the property of exponents:
![(1)/(3)\log (b^2)+(1)/(3)\log c^4-8\log a=(2)/(3)\log (b^{})+(4)/(3)\log c^{}-8\log a](https://img.qammunity.org/2023/formulas/mathematics/college/t5zf28wr7di57ka66507u7kg8t9ma211ye.png)
Now, we substitute the given values for each of the "log":
![(2)/(3)\log (b^{})+(4)/(3)\log c^{}-8\log a=(2)/(3)(-9)+(4)/(3)(-9)-8(-10)](https://img.qammunity.org/2023/formulas/mathematics/college/bogaklqrn83lud4zjkmnx7tvzza0dj0aok.png)
Solving the operations:
![(2)/(3)(-9)+(4)/(3)(-9)-8(-10)=62](https://img.qammunity.org/2023/formulas/mathematics/college/ftllwknpn1xjp4alwu2b6yms6gi3anq349.png)
Therefore, the numerical value of the expression is 62.