甲乙两人共做一道题:(2x+a)*(3x+b).由于甲抄错了a的符号,得到的结果为6x^2+11x-10.乙抄错了x的系

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  • 甲抄错题部份

    (2X-A)(3X+B)=6X^2-(2B-3A)X-AB=6x^2+11x-10

    AB=10

    2B-3A=11,,B=(3A+11)/2

    A(3A+11)/2=10

    3A^2+11A-20=0

    (A+5)(3A-4)=0,,A=-5(B=-2),A=4/3(B=30/4)

    乙抄错题部份

    (HX-5)(KX-2)=HKX+(-5K-2H)X+10=2x^2-9x+10.

    HK=2,,-5K-2H=-9,,K=(9-2H)/5,,H(9-2H)/5=2

    -2H^2+9H-10=0,,2H^2-9H+10=0,,(H-2)(2H-5)=0,

    H=2(K=1),H=5/2(K=4/5)

    (HX+4/3)(KX+30/4)=HKX+(4K/3+30H/4)X+10=2x^2-9x+10.

    HK=2,,4K/3+30H/4=-9,,K=(-9-30H/4)/4,,K=(-18-15H)/8

    H(-18-15H)/8=2

    -15H^2-18H-16=0,此题无解,消

    故A=-5,B=-2

    (2X-5)(3X-2)=6x^2-19x+10