ANSWER
• (g o f)(x) = ,16x² + 24x + 9
,
• B., the domain of g o f is all real numbers
Step-by-step explanation
The composition is,
![(g\circ f)(x)=g(f(x))](https://img.qammunity.org/2023/formulas/mathematics/college/8lu2o6klwimn8usrejj4tq4ax3gg3hc8p3.png)
This means that, to find the composition, we have to replace x with f(x) in the function g(x),
![g(f(x))=(f(x))^2](https://img.qammunity.org/2023/formulas/mathematics/college/7kp0og9fmo2xuhn2ochc31fx9prfedvw9p.png)
Now, replace f(x) with its expression,
![g(f(x))=(4x+3)^2](https://img.qammunity.org/2023/formulas/mathematics/college/6g89i4m2oxpar6z6mc6pnkprvtgngikkmf.png)
We can expand this binomial squared to write it in standard form. The composition is,
![(g\circ f)(x)=16x^2+24x+9](https://img.qammunity.org/2023/formulas/mathematics/college/g9ls6eshnqi0igtik7kip6a3sz1wn1qgai.png)
As we can see, this is a polynomial function. Therefore, the domain is all real numbers.