Question

(a+b+c)(a-b+c)(a+b-c)=?

Answer 1

(a+b+c)(a-b+c)(a+b-c)=((a+b)^2-c^2)(a-b+c)=a^3-a^2b+a^2c-ab^2+2abc-b^3+b^2c-ac^2+bc^2-c^3.