Step 1: First we have to write polynomials in descending order.
$$ \begin{aligned} P(x) &= 4b^2-2 \\ Q(x) &= 4b^2-2b+2 \\ \end{aligned} $$We can multiply polynomials by using a GRID METHOD
Write one of the polynomials across the top and the other down the left side.
$$ \begin{darray}{|c|c|c|c|}\hline & \color{blue}{4b^2} & \color{blue}{-2b} & \color{blue}{2} \\ \hline \color{blue}{4b^2} & & & \\ \hline \color{blue}{-2} & & & \\ \hline \end{darray} $$Fill in each empty box by multiplying the intersecting terms.
$$ \begin{darray}{|c|c|c|c|}\hline & \color{blue}{4b^2} & \color{blue}{-2b} & \color{blue}{2} \\ \hline \color{blue}{4b^2} & \color{orangered}{16b^4} & \color{orangered}{-8b^3} & \color{orangered}{8b^2} \\ \hline \color{blue}{-2} & \color{orangered}{-8b^2} & \color{orangered}{4b} & \color{orangered}{-4} \\ \hline \end{darray} $$Combine like terms:
$$ 16b^4-8b^3-8b^2 + 8b^2 + 4b-4 = \\ 16b^4-8b^3+4b-4 $$