4-4: The Fundamental Theorems Definition: If f is continuous on [ a,b ] and F is an antiderivative of f on [ a,b ], then: The Fundamental Theorem:

Example Evaluate the definite integral using a Riemann Sum the fundamental theorem:

Try This Evaluate the definite integral using the fundamental theorem:

Try This Evaluate the definite integral using the fundamental theorem: 4

Try Me Evaluate the definite integral using the fundamental theorem: 1

Example Find the area bounded by,the x axis, and the lines x =-2 and x =2 -2 2

Try This Find the area bounded by, the x axis, the y axis and the line x = sq. units

Important Idea Provided you can find an antiderivative of f, you can now evaluate a definite integral without using the limit of a Riemann sum.

Try This Evaluate: =0

Assignment /1-21odd

Definition Write this down… If f is continuous on [ a,b ], then there exists a number c in [ a,b ] such that Mean Value Theorem for Integrals:

Analysis f( c) c a b The area of the rectangle is the same as the area under the curve from a to b The area of the rectangle is f (c)(b-a)

Example Find the value c guaranteed by the Mean Value Theorem for Integrals for f(x) over the specified interval: for [1,3]

Warm-Up Find the value c guaranteed by the Mean Value Theorem for Integrals for f(x) over the specified interval: for [1,3]

Definition If f is integrable over [ a,b ], then the average value of f on the interval [ a,b ] is:

Analysis Average Value a b f(x) Average Value Since area is height times width, area divided by width equals height which is average value.

Analysis area divided by width =average value

Example Find the average value of f (x)=4-x 2 on [0,3]

Try me Find the average value of f(x)=x 3 on [1,3]

Important Idea A definite integral is normally a number, but…sometimes it is helpful to write a definite integral as a function.

Example What is different? The answer is a function and not a number.

Example Find the area under and above the x axis and between the vertical lines x =0 & x =1; x =0 & x =2, and x =0 & x =3

Try This Evaluate: For

Definition If f is continuous on an open interval containing a, then for every x in the interval: The 2 nd Fund. Theorem: This is a constant

Example Integrate to find F as a function of x and then demonstrate the second fundamental theorem by differentiating the result:

Important Idea The second fundamental theorem states that the derivative of the integral of a function is the function evaluated at the upper limit of integration.

Definition If f is continuous on an open interval containing a, then for every x in the interval: The 2 nd Fund. Theorem: Chain rule version

Try This Evaluate:

Important Idea

Try This Evaluate:

Assignment /1-21odd odd, odd, odd (slides 15-31)

Lesson Close Name and explain three important theorems mentioned in this lesson.