10x^5-25x^4+30x^3 是不是这样?
=5x^3(x^2-5x+6)
=5x^3(x-2)(x-3)
2a^4-12a^3+18a^2
=2a^2(a^2-6a+9)
=2a^2(a-3)^2
63a^3b-28ab
=7ab(9a^2-4)
=7ab(3a+2)(3a-2)
9a(x-y)^2-18b(y-x)
=9a(x-y)^2+18b(x-y)
=9(x-y)(ax-ay+2b)
(x^2-7)^2-4(x^2-7)+4 是不是这样?
=(x^2-7-2)^2
=(x^2-9)^2
=(x+3)^2(x-3)^2
16(2a+b)^2-9(a-2b)^2
=[4(2a+b)]^2-[3(a-2b)]^2
=(8a+4b+3a-6b)(8a+4b-3a+6b)
=(11a-2b)(5a+10b)
=5(11a-2b)(a+2b)