Question

求大家帮帮忙 有几道不会的因式分解。。谢谢大家。。我很急啊、、

①.-9x²+24xy+6y² ②.y²-x²+10x-25 ③.(a²-9b²)+(a-3b) ④. 2x³-x²+x-1 ⑤.(x-y)(x-y-2)+1 谢谢各位了。。尽量快点。。我很急啊

Answer 1

①.-9x²+24xy+6y²
=-3(3x²-8xy-2y²)

②.y²-x²+10x-25
=y²-(x-5)²
=(y-x+5)(y+x-5)

③.(a²-9b²)+(a-3b)
=(a-3b)(a+3b)+(a-3b)
=(a-3b)(a+3b+1)

④. x³-x²+x-1
=x²(x-1)+(x-1)
=(x-1)(x²+1)

⑤.(x-y)(x-y-2)+1
=(x-y)²-2(x-y)+1
=(x-y-1)²