a³-5a²b-66ab² -5ab应该是-5a²b吧.
=a(a²-5ab-66b²)
=a(a-11b)(a+5b)
x^5-13x^3y^2+36xy^4
=x(x⁴-13x²y²+36y⁴)
=x(x²-4y²)(x²-9y²)
=x(x+2y)(x-2y)(x+3y)(x-3y)
m²-4n²-2m-4n
=(m+2n)(m-2n)-2(m+2n)
=(m+2n)(m-2n-2)
3a^3-3ab²+6a^2b-3ab^2
=3a(a²-b²+2ab-b²)
=3a(a²+2ab+b²-3b²)
=3a[(a+b)²-3b²]
=3a[a+(1+√3)b][a+(1-√3)b] 这题怀疑抄错了.
x^2-3xy-4y^2-2x-2y
=(x-4y)(x+y)-2(x+y)
=(x+y)(x-4y-2)