What is the product of - 2x^3+x-5 and x^3-3x-4?

To find the product of - 2x^3+x-5 and x^3-3x-4, we need to multiply each term in the first polynomial by the second polynomial. (So, x^3 - 3x - 4) times ...

-2x^3 = - 2x^6 + 6x^4 + 8x^3

x = x^4 - 3x^2 - 4x

-5 = - 5x^3 + 15x + 20

If we add all these together, we get (-2x^6 + 7x^4 + 3x^3 - 3x^2 + 11x + 20)