The sum of two polynomials is 8d5 – 3c3d2 + 5c2d3 – 4cd4 + 9. if one addend is 2d5 – c3d2 + 8cd4 + 1, what is the other addend?

To solve for the the other addend, subtract the given addend from the given sum of the two polynomials,
                (8d^5 - 3c³d² + 5c²d³ - 4cd^4 +9)   -     (2d^5 - c³d² + 8cd^4 + 1)

Subtracting the terms from their like terms of the sum gives and answer of 
                        6d^5 - 2c³d² + 5c²d³ - 12cd^4 +8

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