The Difference Quotient 1.1

The difference quotient easy to apply once you know the steps. For a given expression substitute x+h for your value instead of x and subtract your original expression. 

Ex.  

 

  turns into                                                  

Then distribute the -2 and combine like terms. The end result should look like this.

The answer is -2 but to make this simplified version equivalent to the original you must include 

Ex. 2 

Substitute both 5+h and 5 into the function given. so it looks like this with the red numbers the part substituted in. 

Then Distribute and add like terms until you get to the final answer.

the final answer should look like this.

Thats all there is to doing difference quotients. Hopefully you understand from these two examples but if not there are multiple videos which go over the same topic.

The difference quotient:

http://www.youtube.com/watch?v=1O5NEI8UuHM

Precalculus- Computing Difference Quotients:

http://www.youtube.com/watch?v=AQatV_NJOsA

Pre-Calculus - Evaluating the difference quotient:

http://www.youtube.com/watch?v=OXXrsxA4f_4