Answer:
We have
`log(1+x+x^(2))=logP{(1-wx)(1-w^(2)x)}`
`rarr log(1+x+x^(2))=log(1-wx)+log(1-w^(2)x)`
`rarr log(1+x+x^(2))=log(1-wx)+log(1-w^(2)x)`
`rarr log(1+x+x^(2))=-underset(r=1)overset(infty)Sigma(w^(r )+w^(2r))(x^(r ))/(r )`
`therefore "coefficient of" x^(n) log(1+x+x^(2))` is equal to
`-(1)/(n)(w^(n)+w^(2n))=(2)/(n)`