Describe the graph

Question

Given f(x)= x²-4 , describe the graph at x=-2

x+2

Answer 1

(x^2 - 4) / (x+2) = (x+2)(x-2)/(x+2) = x-2

So at x=-2, the linear function is f(-2) = -2-2 = -4.

It is a line which crosses the y-axis at (0,-2) and has slope 1.

It contains (1,-1) and (2,0), which is the x-intercept.

Some older function plotters will treat x=-2 with an OPEN

circle at (-2,0) signifying the REMOVABLE discontinuity