This Geogebra model to the right allows us to see how a secant line to a graph can be used to find the average rate of change of a graph around a certain point or between two values.

Enter your equation into the white box and then slide the BLUE and RED points to find the secant line.

This HTML5 model (that I created) demonstrates how we visualize what a limit represents. (Thank you W3Schools for your HTML5 + JS crash course) 

The RED and GREEN points represent what the function is "crashing to" on the left and right sides of x=2 .  Because they are BOTH going to the same value from the left and right directions, we can say that the limit EXISTS. 

This HTML5 model (that I created) demonstrates how we visualize what a limit represents. (Thank you W3Schools for your HTML5 + JS crash course) 

The RED and GREEN points represent what the function is "crashing to" on the left and right sides of x=2 .  Because they are DO NOT go to the same value from the left and right directions, we can say that the limit DOES NOT EXISTS. 

This HTML5 model (that I created) demonstrates how we visualize what a limit represents. (Thank you W3Schools for your HTML5 + JS crash course) 

The RED and GREEN points represent what the function is "crashing to" on the left and right sides of x=3 .  Because they are DO NOT go to the same value from the left and right directions, we can say that the limit DOES NOT EXISTS.    This types is called a JUMP DISCONTINUITY

This HTML5 model (that I created) demonstrates how we visualize what a limit represents. (Thank you W3Schools for your HTML5 + JS crash course) 

The RED and GREEN points represent what the function is "crashing to" on the left and right sides of x=0 .  Because they are BOTH going to the same value from the left and right directions, we can say that the limit EXISTS.