Jawabanmu

2014-08-30T19:06:41+07:00
(x+y) (3x²+xy+2y²)=x(3x²+xy+2y²)+y(3x²+xy+2y²)
=3x³+x²y+2xy²+3yx²+xy²+2y³
=3xy³+x²y+2xy²+xy²+3yx²+2y³
=3xy³+x²y+3xy²+3yx²+2y³