求助一题，我用了十字相乘来做结果和常规的方法的答案不一样
\u5341\u5b57\u76f8\u4e58\u7ec3\u4e60\u98982x2\uff0d5x\uff0d12
\u51c9\u5c71~\u8fd9\u4e9bX\u540e\u9762\u76842\u90fd\u662f\u5e73\u65b9\u7684\u610f\u601d\u4e48\uff1f
\u5341\u5b57\u76f8\u4e58\u6211\u5012\u662f\u4f1a\uff0c\u4e0d\u8fc7\u4f60\u7684\u610f\u601d\u548c\u683c\u5f0f\u786e\u5b9e\u6ca1\u600e\u4e48\u660e\u767d\uff0c(\u6bd4\u5982\u4e0d\u8981\u8fd9\u4e9b\u9898\u662f\u4ec0\u4e48\u610f\u601d\u2026\u2026)\u5148\u505a\u524d\u516d\u4e2a\u7ed9\u4f60\u5427~
\u770b\u5230\u7684\u8bdd\u95ee\u9898\u8865\u5145\uff0c\u7136\u540e\u6211\u4f1a\u628a\u540e\u9762\u7684\u90fd\u4e00\u4e00\u8865\u5168
\u53e6\u5916\u2026\u2026\u4f60\u4eec\u8001\u5e08\u6ca1\u6709\u8bb2\u539f\u7406\u4e48\u2026\u2026
(1)2x2\uff0d5x\uff0d12
=\uff082x+3)(x-4)
(2)3x2\uff0d5x\uff0d2
=(3x+1)(x-2)
(3)6x2\uff0d13x+5
=\uff082x-5\uff09(3x+1)
(4)7x2\uff0d19x\uff0d6
=(7x+2)(x-3)
(5)12x2\uff0d13x+3
=(3x-1)(4x-3)
(6)4x2+24x+27
=(2x+3)(2x+9)
(1)2x2\uff0d5x\uff0d12\uff1b (2)3x2\uff0d5x\uff0d2\uff1b
(3)6x2\uff0d13x+5\uff1b (4)7x2\uff0d19x\uff0d6\uff1b
(5)12x2\uff0d13x+3\uff1b (6)4x2+24x+27.
(1)6x2\uff0d13xy+6y2\uff1b (2)8x2y2+6xy\uff0d35\uff1b
(3)18x2\uff0d21xy+5y2\uff1b (4)2(a+b) 2+(a+b)(a\uff0db)\uff0d6(a\uff0db) 2.
(1)2x2+3x+1\uff1b (2)2y2+y\uff0d6\uff1b
(3)6x2\uff0d13x+6\uff1b (4)3a2\uff0d7a\uff0d6\uff1b
(5)6x2\uff0d11xy+3y2\uff1b (6)4m2+8mn+3n2\uff1b
(7)10x2\uff0d21xy+2y2\uff1b (8)8m2\uff0d22mn+15n2.
(1)4n2+4n\uff0d15\uff1b (2)6a2+a\uff0d35\uff1b
(3)5x2\uff0d8x\uff0d13\uff1b (4)4x2+15x+9
(5)15x2+x\uff0d2\uff1b (6)6y2+19y+10\uff1b
(7)20\uff0d9y\uff0d20y2\uff1b (8)7(x\uff0d1) 2+4(x\uff0d1)(y+2)\uff0d20(y+2)
(1) 12x^2+10xy-12x+5y-9
(2) 2y^2-ay-3by-a^2+b^2
(3) x^3+(2a+1)^2+(a^2+2a-1)
(4)a^2+b^2-2ab-2a+2b-8
当时做的时候把获得100%的利润和折扣率弄混了o(∩_∩)o...
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