Completing the squares of a multivariable function

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
1 reply · 2K views
pondzo
Messages
168
Reaction score
0

Homework Statement



completing the squares; ## x^2+y^2+2xy-2x-2y+43 = 0##

The Attempt at a Solution



I did it as follows, but i would like to know if there is a different 'nicer' method to complete it;

## x^2 + y^2 + 2xy − 2x − 2y + 43 ##

## = (x + y)^2 − 2x − 2y + 43 ##

## = (x + y)^2 − 2(x + y) + 43 ##

## = (x + y)^2 − 2(x + y) + 1 + 42 ##

## = ((x + y) − 1)^2 + 42 ##
 
Physics news on Phys.org
pondzo said:

Homework Statement



completing the squares; ## x^2+y^2+2xy-2x-2y+43 = 0##

The Attempt at a Solution



I did it as follows, but i would like to know if there is a different 'nicer' method to complete it;

## x^2 + y^2 + 2xy − 2x − 2y + 43 ##

## = (x + y)^2 − 2x − 2y + 43 ##

## = (x + y)^2 − 2(x + y) + 43 ##

## = (x + y)^2 − 2(x + y) + 1 + 42 ##

## = ((x + y) − 1)^2 + 42 ##
That looks plenty "nice" to me !