运用乘法公式计算 速求,要有过程(x-3))(x+3)(x²+9))(x-1)(x+1)(x+2y-3)(x-2y-3)(x+y)²(x-y)²(m-n+3)(m+n-3)

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运用乘法公式计算 速求,要有过程(x-3))(x+3)(x²+9))(x-1)(x+1)(x+2y-3)(x-2y-3)(x+y)²(x-y)²(m-n+3)(m+n-3)

运用乘法公式计算 速求,要有过程(x-3))(x+3)(x²+9))(x-1)(x+1)(x+2y-3)(x-2y-3)(x+y)²(x-y)²(m-n+3)(m+n-3)
运用乘法公式计算 速求,要有过程
(x-3))(x+3)(x²+9))
(x-1)(x+1)
(x+2y-3)(x-2y-3)
(x+y)²(x-y)²
(m-n+3)(m+n-3)

运用乘法公式计算 速求,要有过程(x-3))(x+3)(x²+9))(x-1)(x+1)(x+2y-3)(x-2y-3)(x+y)²(x-y)²(m-n+3)(m+n-3)

主要是用到平方差公式及完全平方公式.
(x-3))(x+3)(x²+9))=(x²-9)(x²+9)=x^4-81
(x-1)(x+1)=x²-1
(x+2y-3)(x-2y-3)=((x-3)+2y)((x-3)-2y)=(x-3)^2-4y^2=x^2-4y^2-6x+9
(x+y)²(x-y)²=((x+y)(x-y))²=(x^2-y^2)^2=x^4-2x^2y^2+y^4
(m-n+3)(m+n-3)=(m-(n-3))(m+(n-3))=m^2-(n-3)^2=m^2-n^2+6n-9

(x-3))(x+3)(x²+9)=x^4-81
(x-1)(x+1)=x^2-1
(x+2y-3)(x-2y-3)=(x-3)^2-4y^2=x^2-6x-4y^2+9
(x+y)²(x-y)²=x^4-2(xy)^2+y^4
(m-n+3)(m+n-3)=m^2-n^2+6n-9