Answer :
By subtracting the given addend to the sum, we see that the other addend is:
[tex]6d^5 - 2c^3d^2 + 5c^2d^3 - 12cd^4 - 8[/tex]
How to get the other addend?
We know that the sum of two polynomials is:
[tex]8d^5 - 3c^3d^2 + 5c^2d^3 - 4cd^4 + 9[/tex]
One of the addends is:
[tex]2d^5 - c^3d^2 + 8cd^4 + 1[/tex]
To get the other addend, we can subtract the given addend to the sum:
[tex]8d^5 - 3c^3d^2 + 5c^2d^3 - 4cd^4 + 9 - (2d^5 - c^3d^2 + 8cd^4 + 1)\\\\6d^5 - 2c^3d^2 + 5c^2d^3 - 12cd^4 - 8[/tex]
Then we can conclude that the other addend is:
[tex]6d^5 - 2c^3d^2 + 5c^2d^3 - 12cd^4 - 8[/tex]
If you want to learn more about polynomials:
https://brainly.com/question/4142886
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