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5x³-6x²+15x-28
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x+2) 5x⁴+ 4x³+3x²+2x+1
5x⁴+10x³
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-6x³ +3x²+2x+1
-6x-12x²
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15x²+2x+1
15x²+30x
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-28x+1
-28x-56
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57
∴5x⁴+ 4x³+3x²+2x+1=(x+2)*(5x³-6x²蚂冲+15x-28)+57
余闷肢歼数饥并是57