2x⁴+7x³-3x²-5x-1=0
x₁=1
2x⁴+7x³-3x²-5x-1 I_x-1_
2x⁴-2x³ I 2x³+9x²+6x+1
----------
9x³-3x²
9x³-9x²
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6x²-5x
6x²-6x
----------
x-1
x-1
-------
0
2x³+9x²+6x+1=0
x₂=-0,5
2x³+9x²+6x+1 I_x+0,5_
2x³+x² I 2x²+8x+2
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8x²+6x
8x²+4x
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2x+1
2x+1
--------
0
2x²+8x+2=0 I÷2
x²+4x+1=0 D=12=2√3
x₃=-2+√3 x₄=-2-√3.