Question

I'd really appreciate it if someone could help me with this question? I don't know why, but I'm sorta struggling with it.

Answer 1

                          5x        -6
-3x^3 + 2x^2                                      (Note how I changed the signs.)
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-3x^3  + 2x^2 + 5x - 6          (this is the "difference" that you wanted.

Answer 2

$-3x^3+2x^2+5x-6$