Jawabanmu

2015-06-28T22:07:06+07:00
( x+y)(2x+y) = (2x^2+3xy+y^2)(x+2y) = 2x^3+4x^2y+3x^2y+3xy^2+xy^2+2y^3=2x^3+7x^2y+4xy^2+2y^3