帮忙用因式分解法解下列方程.麻烦写出解题过程与思路.①x^2-y^2+a^2-b^2+2ax+2by ②4-(x^2-4x+2)^2③a^2-ab+ac-bc ④m^2-5m-mn+5n⑤x^2-x-12

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帮忙用因式分解法解下列方程.麻烦写出解题过程与思路.①x^2-y^2+a^2-b^2+2ax+2by ②4-(x^2-4x+2)^2③a^2-ab+ac-bc ④m^2-5m-mn+5n⑤x^2-x-12

帮忙用因式分解法解下列方程.麻烦写出解题过程与思路.①x^2-y^2+a^2-b^2+2ax+2by ②4-(x^2-4x+2)^2③a^2-ab+ac-bc ④m^2-5m-mn+5n⑤x^2-x-12
帮忙用因式分解法解下列方程.麻烦写出解题过程与思路.
①x^2-y^2+a^2-b^2+2ax+2by ②4-(x^2-4x+2)^2
③a^2-ab+ac-bc ④m^2-5m-mn+5n
⑤x^2-x-12

帮忙用因式分解法解下列方程.麻烦写出解题过程与思路.①x^2-y^2+a^2-b^2+2ax+2by ②4-(x^2-4x+2)^2③a^2-ab+ac-bc ④m^2-5m-mn+5n⑤x^2-x-12
①x^2-y^2+a^2-b^2+2ax+2by
=x^2+2ax+a^2-b^2+2by-y^2
=(x+a)^2-(b-y)^2
=(x+a+b-y)(x+a-b+y)
②4-(x^2-4x+2)^2
=(2+x^2-4x+2)(2-x^2+4x-2)
=(x^2-4x+4)(-x^2+4x)
=[(x-2)^2][-x(x-4)]
=-x(x-2)^2(x-4)
③a^2-ab+ac-bc
=a(a-b)+c(a-b)
=(a-b)(a+c)
④m^2-5m-mn+5n
=m(m-5)-n(m-5)
=(m-5)(m-n)
⑤x^2-x-12
=(x-4)(x+3)

①x^2-y^2+a^2-b^2+2ax+2by
=x²+2ax+a²-(y²-2by+b²)=(x+a)²-(y-b)²=(x+a+y-b)(x+a-y+b)
②4-(x^2-4x+2)^2=2²-(x^2-4x+2)^2=(2+x^2-4x+2)(2-x²+4x-2)=(x-2)...

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①x^2-y^2+a^2-b^2+2ax+2by
=x²+2ax+a²-(y²-2by+b²)=(x+a)²-(y-b)²=(x+a+y-b)(x+a-y+b)
②4-(x^2-4x+2)^2=2²-(x^2-4x+2)^2=(2+x^2-4x+2)(2-x²+4x-2)=(x-2)²(4x-x²)=x(x-2)²(4-x)
③a^2-ab+ac-bc=a(a-b)+c(a-b)=(a-b)(a+c)
④m^2-5m-mn+5n=(m²-mn)-(5m-5n)=m(m-n)-5(m-n)=(m-n)(m-5)
⑤x^2-x-12=(x-4)(x+3) (十字相乘因式分解)

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1.(x-a)^2-(y-b)^2