Answer:
-2x^6 + 7x^4 + 3x^3 - 3x^2 + 11x + 20
Step-by-step explanation:
When multiplying two expressions, each part of the expression has to be multiplied by each part of the other expression.
(-2x^3 + x - 5) * (x^3 - 3x - 4)
Let's multiply -2x^3 first.
-2x^3 * x^3 = -2x^6
-2x^3 * -3x = 6x^4
-2x^3 * -4 = 8x^3
Now let's multiply x.
x * x^3 = x^4
x * -3x = -3x^2
x * -4 = -4x
Finally, let's multiply -5.
-5 * x^3 = -5x^3
-5 * -3x = 15x
-5 * -4 = 20
Let's put all of our answers into one expression in descending order of exponents.
-2x^6 + 6x^4 + x^4 + 8x^3 - 5x^3 - 3x^2 - 4x + 15x + 20
Combine like terms:
-2x^6 + 7x^4 + 3x^3 - 3x^2 + 11x + 20
