(x的平方-4x-12)(x的平方-4x+3)+5

2个回答

(x的平方-4x-12)(x的平方-4x+3)+56
=(x²-4x)²-9(x²-4x) -36+56
=(x²-4x)²-9(x²-4x)+20
=(x²-4x+4)(x²-4x+5)
=(x-2)²(x²-4x+5)