越快越好（a²+9b²-1）²-36a²b²7x²-3y+xy-21xabx²+bxy-axy-y²x4+1/4y4a5+a4+1x²+ax²+x+ax-1-a

Question

越快越好
（a²+9b²-1）²-36a²b²
7x²-3y+xy-21x
abx²+bxy-axy-y²
x4+1/4y4
a5+a4+1
x²+ax²+x+ax-1-a

Answer 1

(a²+9b²-1)²-36a²b²
=(a²+9b²-1)²-(6ab)²
=(a²+9b²-1+6ab)(a²+9b²-1-6ab)²
=(a+3b+1)(a+3b-1)(a-3b+1)(a-3b-1)
7x²-3y+xy-21x
=(7x²-21x)-(xy-3y)
=7x(x-3)-y(x-3)
=(x-3)(7x-y)
abx²+bxy-axy-y²
=bx(ax+y)-y(ax+y)
=(ax+y)(bx-y)
x²+ax²+x+ax-1-a
=x²(1+a)+x(1+a)-(1+a)
=(1+a)(x²+x-1)