(X平方-2X)的平方-7(X平方-2X)+12
=(x²-2x-3)(x²-2x-4)
=(x-3)(x+1)(x²-2x+1-5)
=(x-3)(x+1)[(x-1)²-5]
=(x-3)(x+1)(x-1+√5)(x-1-√5)
(x^2-2x)^2-7(x^2-2x)+12
=(x^2-2x-3)(x^2-2x-4)
=(x-3)(x+1)((x-1)^2-5)
=(x-3)(x+1)(x-1-√5)(x-1+√5)
(X-3)*(X-4)*(X平方-2X-4)
(x^2-2x-4)(x+1)(x-3)