The \(xy\)-plane is the two dimensional space spanned by two copies of the real number line referred to as the \(x\)-axis and the \(y\)-axis. Any point in the \(xy\)-plane can be specified by its coordinates \((x,y) = (a,b)\) where \(a\) is how far left/right the point is in the \(x\)-direction and \(b\) is how far upwards/downwards the point is in the \(y\)-direction. The point \((0,0)\) is called the origin.
The graph of a function \(f\) is the set of all input-output pairs \((x,y)\) for which \(y = f(x).\) For a function \(f\) with real inputs and real outputs, we can plot its graph in the \(xy\)-plane.
HALF OF MLK LECTURE scatter plot function domain range independent variable dependent variable Function notation \(f(x)\) (not multiplication) modelling Complete graph OR viewport