Answers

2015-01-04T22:56:14+08:00
20x^2+9x-10 - 15x^2-5x+3 = 5x^2+4x-7
3x^2-4x+2 - x^2-x-1 = 2x^2-5x+1

(5x^2+4x-7)(2x^2-5x+1)=10x^4-25x^3+5x^2+8x^3-20x^2+4x-14x^2+35x-7
                                  = 10x^4-17x^3-29x^2+39x-7
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