Step 1: First we have to write polynomials in descending order.

$$ \begin{aligned} P(x) &= -4x^2 \\ Q(x) &= 2x^4-x^3-3x-2 \\ \end{aligned} $$

We can use distribution property to multiply the polynomial by the monomial.

$$ \begin{aligned} \color{blue}{-4x^2} \cdot \left( 2x^4-x^3-3x-2 \right) &= \color{blue}{-4x^2} \cdot 2x^4 + \color{blue}{-4x^2} \cdot \left( -x^3\right) + \color{blue}{-4x^2} \cdot \left( -3x\right) + \color{blue}{-4x^2} \cdot \left( -2\right) = \\ &= -8x^6+4x^5+12x^3+8x^2 \end{aligned} $$

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