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Need help with this ASAP! thank you!

Need help with this ASAP! thank you!-example-1

1 Answer

1 vote

Answer:

-4x^3 + 9x^2+35x -45

Explanation:

The notation (f*g)(x) actually just means f(x)*g(x)

We just substitute what f(x) is and what g (x) is

(4x-9) * (-x^2 - 3x + 5 )

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

4x * -3x = -12x

4x*5 = 20x

-4x^3 + -12x+20x

and

-9 * -x^2 = 9x^2

-9*-3x = 27x

-9*5 = -45

-4x^3 + -12x+20x + 9x^2 + 27x +-45

Now to put this in standard form, we have to order it with the terms with the highest exponents to the ones with the lowest exponents

-4x^3 + 9x^2 -12x+20x+27x -45

-12x+20x+27x

-12x+47x

35x

-4x^3 + 9x^2+35x -45

-45 goes last because it is equal to -45x^0

User MStew
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