(3x +5 )(2x² +9x -5) utilizamos ley de signos +*+ = +, -*- = +, -*+ = -, +* - = -
2x² +9x -5
3x +5
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10x² +45x -25
6x³+27x² -15x
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6x³ +37x²+30x -25
(7x -4 ) (x³ -x² +6)
x³ -x² +6
7x - 4
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-4x³ +4x³ -24
7x⁴ -7x³ +42x
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7x⁴ -11x³ +4x² +42x -24