Graph

The graph of a function $f:X\to Y$ is the subset $f=\{x,f(x):x\in X\}\subset X\times Y$

Examples

• The graph of $f(x)=x^2$ is a subset of $\mathbb{R}\times \mathbb{R}={\mathbb{R}}^2$
• The graph of $g(x,y)=x^2+y^2+1$ is a subset of ${\mathbb{R}}^2\times \mathbb{R}={\mathbb{R}}^3$