Find the sum of n terms of the series
`(x+y)+(x^(2)+xy+y^(2))+(x^(3)+x^(2)y+xy^(2)+y^(3))+...`

Find the sum of n terms of series (x+y)+(x^(2)+xy+y^(2))+(x^(3)+x^(2)y+xy^(2)+y^(3))+...

Find the sum of n terms of the series (x+y)+(x^(2)+2y)+(x^(3)+3y)+...

Find the sum of n terms of the series (x+y)+(x^(2)+2y)+(x^(3)+3y)+...

Find the sum of n terms of series (x+y) + (x^2+ xy +y^2)+(x^3+x^2y+xy^2+y^3)+..................

Find the sum of n terms of series (x+y) + (x^2+ xy +y^2)+(x^3+x^2y+xy^2+y^3)+..................

Find the sum of n terms of series (x+y) + (x^2+ xy +y^2)+(x^3+x^2y+xy^2+y^3)+..................

If |x|<1 and |y|<1, find the sum of infinity of the following series: (x+y)+(x^(2)+xy+y^(2))+(x^(3)+x^(2)y+xy^(2)+y^(3))+

x^(3) + x^(2)y+ xy^(2) + y^(3) = 81

Find the sum to n terms of the sequence : (i) (x+1/x)^(2)+ (x^(2)+1/x^(2))^(2)+ (x^(3)+1/x^(3))^(2) ... to n terms (ii) (x+y)+ (x^(2)+xy+y^(2))+(x^(3)+x^(2)y+xy^(2)+y^(3)) , ... to n terms