X²+2xy+y²=?

1 Answer
Jun 13, 2018

#x^2+2xy+y^2 = (x+y)^2#

Explanation:

It is not exactly clear what the questioner had in mind here.
I will assume we are to simplify the expression (and that #X=x#)

#f(x,y) = x^2+2xy+y^2#

#f(x,y)# is the well known expansion of #(x+y)^2#

Check: #(x+y)(x+y) = x^2 + xy +yx +y^2#

#= x^2+2xy+y^2#