3x^2 + 5x - 2
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x^2 + 1 ) 3x^4 + 5x^3 + x^2 + 5x - 2
3x^4 + 3x^2
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5x^3 - 2x^2
5x^3 + 5x
-------------------------
- 2x^2 - 2
- 2x^2 - 2
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............
The answer is 3x^2 + 5x - 2