Calculus

Lesson 23 The Fundamental Theorem of Calculus

and The Mean Value Theorem for Integrals

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           FTC:   ,

 

                                                where  is the antiderivative of  and

                                                 is continuous on

 

 

 

 

                        Examples:    

 

 

 

                        MVT for integrals:  remember that MVT tells us that there was a point on the

                                    curve with the same slope as the average slope.

 

 

                                    MVT for integrals tells us that there is a point on the function such that

                                    the area found by  is the same as the area under the curve

                                     from  to .

 

                        Formally, we say that there exists  such that

                        as long as  is continuous on .

 

            What this is saying is that we can find a rectangle that has the same area as the curve.  The      

            widths are the same.  We can find  such that the height is .

 
 

             Note that there could be more than one value for .

 

 

            We call  the average value of the function.  Using MVT for integrals, we can then find

            the average value of the function by dividing both sides by .

 

 

                                                                                 

 

 

            Example:  Find the average value of  on the interval .

            Example:  Find the average value of  on the interval .

 

                                                                                    Check for it to be continuous!!!!

  

 

            Lastly, we have the 2nd Fundamental Theorem of Calculus:

 

                            (derive by using FTC)

 

 

                        This can be interpreted as figuring out how the area is changing! 

 

 

 

            Let  g  be a continuous function on an interval, such that    and  .       

 

(a)       What is the largest possible domain for  ?

 

(b)       Write an expression for  .

 

(c)       

 

(d)      

 

On to Lesson 24 - Integration by Substitution

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