Practice problem
What is
x2+y2x^2+y^2x2+y2
x2+y2+xy+yx^2+y^2+xy+yx2+y2+xy+y
x2−y−xyx^2-y-xyx2−y−xy
x+xy+yx+xy+yx+xy+y
Type a concept, like “slope” or “photosynthesis”.
