Question

a的四次方+2a的三次方b+3a的平方b的平方+2ab的三次方+b的四次方

Answer 1

a^4+2a^3b+3a^2b^2+2ab^3+b^4

=a^4+2a^2b^2+b^4+2a^3b+2ab^3+a^2b^2

=(a^2+b^2)^2+2ab(a^2+b^2)+a^2b^2

=(a^2+b^2+ab)^2