Question

因式分解a^4n-a^3nb^m+a^nb^3m-b^4m

Answer 1

原式=(a^4n-a^3nb^m)+(a^nb^3m-b^4m)

=a^3n(a^n-b^m)+b^3m(a^n-b^m)

=(a^n-b^m)(a^3n+b^3m)

=(a^n-b^m)(a^n+b^m)(a^2n-a^nb^m+b^2m)