Return to site

3.7 Continuity And Differentiablityap Calculus

broken image


Calculus Introduction: Continuity and Differentiability Notes, Examples, and Practice Quiz (w/solutions) Topics include definition of continuous, limits and asymptotes, differentiable function, and more. Hint: The hardest part of these problems for most students is just getting started. First, you need to determine the value of 'M' that you need to use and then actually use the Intermediate Value Theorem. So, go back to the IVT and compare the conclusions of the theorem and it should be pretty obvious what the M should be and then just check that the hypothesis (i.e. The 'requirements. Continuity in Calculus: Definition, Examples & Problems. If I round 3.7, I get 4. Well here, if I graph f(x) as a function of x, I have to pick my finger up. In fact, I need to pick my finger.

Show Mobile Notice
Continuity
Show All NotesHide All Notes
You appear to be on a device with a 'narrow' screen width (i.e. you are probably on a mobile phone). Due to the nature of the mathematics on this site it is best views in landscape mode. If your device is not in landscape mode many of the equations will run off the side of your device (should be able to scroll to see them) and some of the menu items will be cut off due to the narrow screen width.

Section 2-9 : Continuity

13. Use the Intermediate Value Theorem to show that (25 - 8{x^2} - {x^3} = 0) has at least one root in the interval (left[ { - 2,4} right]). Note that you are NOT asked to find the solution only show that at least one must exist in the indicated interval,

Hint : The hardest part of these problems for most students is just getting started.
First, you need to determine the value of 'M' that you need to use and then actually use the Intermediate Value Theorem. So, go back to the IVT and compare the conclusions of the theorem and it should be pretty obvious what the M should be and then just check that the hypothesis (i.e. the 'requirements' of the theorem) are met and you'll pretty much be done.
Show Solution

Okay, let's start off by defining,

3.7 Continuity And Differentiablityap Calculus Calculator

[fleft( x right) = 25 - 8{x^2} - {x^3}hspace{0.5in} & ,hspace{0.25in},M = 0]

The problem is then asking us to show that there is a (c) in (left[ { - 2,4} right]) so that,

3.7 Continuity And Differentiablityap Calculus Solver

[fleft( c right) = 0 = M]

but this is exactly the second conclusion of the Intermediate Value Theorem. So, let's see that the 'requirements' of the theorem are met.

First, the function is a polynomial and so is continuous everywhere and in particular is continuous on the interval (left[ { - 2,4} right]). Note that this IS a requirement that MUST be met in order to use the IVT and it is the one requirement that is most often overlooked. If we don't have a continuous function the IVT simply can't be used.

Now all that we need to do is verify that (M) is between the function values as the endpoints of the interval. So,

3.7 Continuity And Differentiablityap Calculus Algebra

[fleft( { - 2} right) = 1hspace{0.5in}hspace{0.25in}fleft( 4 right) = - 167]

Therefore, we have,

[fleft( 4 right) = - 167 < 0 < 1 = fleft( { - 2} right)]

So, by the Intermediate Value Theorem there must be a number (c) such that,

[ - 2 < c < 4hspace{0.5in}& hspace{0.5in}fleft( c right) = 0]

and we have shown what we were asked to show.


Introduction

In Section 1.2, we learned about how the concept of limits can be used to study the trend of a function near a fixed input value. As we study such trends, we are fundamentally interested in knowing how well-behaved the function is at the given point, say (x = a). In this present section, we aim to expand our perspective and develop language and understanding to quantify how the function acts and how its value changes near a particular point. Beyond thinking about whether or not the function has a limit (L) at (x = a), we will also consider the value of the function (f (a)) and how this value is related to (lim_{x→a} f (x)), as well as whether or not the function has a derivative (f '(a)) at the point of interest. Throughout, we will build on and formalize ideas that we have encountered in several settings.

We begin to consider these issues through the following preview activity that asks you to consider the graph of a function with a variety of interesting behaviors.

Preview Activity (PageIndex{1})

A function (f) defined on (−4 < x < 4) is given by the graph in Figure 1.7.1. Use the graph to answer each of the following questions. Note: to the right of (x = 2), the graph of (f) is exhibiting infinite oscillatory behavior similar to the function (sin( frac{π}{ x })) that we encountered in the key example early in Section 1.2.

(a) For each of the values (a) = −3, −2, −1, 0, 1, 2, 3, determine whether or not (lim_{x→a} f (x)) exists. If the function has a limit (L) at a given point, state the value of the limit using the notation (lim_{x→a} f (x)= L). If the function does not have a limit at a given point, write a sentence to explain why.

3.7 Continuity And Differentiablityap Calculus 14th Edition

Figure (PageIndex{1}): The graph of (y = f (x)).

(b) For each of the values of a from part (a) where (f) has a limit, determine the value of (f (a)) at each such point. In addition, for each such a value, does (f (a)) have the same value as (lim_{x→a} f (x)) ?

(c) For each of the values (a) = −3, −2, −1, 0, 1, 2, 3, determine whether or not (f '(a)) exists. In particular, based on the given graph, ask yourself if it is reasonable to say that f has a tangent line at ((a, f (a))) for each of the given (a)-values. If so, visually estimate the slope of the tangent line to find the value of (f '(a)).





broken image