$#Dino$
`P+Q=2x^5-5x^4-x^3+x^2-x-1+x^4+x^3+5x+2`
`=2x^5+(-5x^4+x^4)+(-x^3+x^3)+x²+(-x+5x)+(-1+2)`
`=2x^5-4x^4+4x+1`
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`P-Q=2x^5-5x^4-x^3+x^2-x-1-x^4-x^3-5x-2`
`=2x^5+(-5x^4-x^4)+(-x^3-x^3)+x²+(-x-5x)+(-1-2)`
`=2x^5-6x^4-2x^3+x²-6x-3`