/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 35 Evaluate the following limits. ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Evaluate the following limits. $$\lim _{x \rightarrow 2} \frac{x^{2}-4 x+4}{\sin ^{2}(\pi x)}$$

Short Answer

Expert verified
Answer: The value of the limit is \(0\).

Step by step solution

01

Factor the numerator

First, we need to factor the numerator. In this case, we can see that it is a quadratic trinomial, of the form \((x-a)^2\), where \(a=2\). Thus, the expression can be written as follows: $$\frac{(x-2)^2}{\sin^2(\pi x)}$$ The next step will be addressing the denominator.
02

Manipulate the denominator

As previously mentioned, we need to manipulate the denominator, so as to avoid direct substitution of \(x\to2\). Notice that the denominator is \(\sin^2(\pi x)\). Let's rewrite the limit using this observation: $$\lim_{x\rightarrow 2} \frac{(x - 2)^2}{\left(\sin^2(\pi x)\right)}$$
03

Apply the Squeeze theorem

To make use of the Squeeze theorem, we have to find an inequality involving the target function, so that we can find the limit. Here, for a small neighborhood near \(x=2\), the range of \(\sin (\pi x)\) must be between \(-1\) and \(1\) (inclusive). Noticing that \(x^2\geq 0\), we can write the inequality as follows: $$0 \leq \frac{(x-2)^2}{\left(-1\right)} \leq \sin^2(\pi x) \leq \frac{(x-2)^2}{\left(1\right)}$$ This inequality applies for values of \(x\) near \(2\), but not equal to \(2\). Now, we can apply limits on all parts of the inequality: $$\lim_{x\rightarrow 2} 0 \leq \lim_{x\rightarrow 2} \frac{(x-2)^2}{\left(-1\right)} \leq \lim_{x\rightarrow 2} \sin^2(\pi x) \leq \lim_{x\rightarrow 2} \frac{(x-2)^2}{\left(1\right)}$$
04

Calculate the limits

Now, let's calculate the limits: $$0 \leq \lim_{x\rightarrow 2} \frac{(x-2)^2}{\left(-1\right)} = 0 $$ $$0 \leq \lim _{x\rightarrow 2}\sin^2(\pi x)$$ $$0 \leq \lim_{x\rightarrow 2} \frac{(x-2)^2}{\left(1\right)} = 0 $$ When both left and right limit equal to zero, we can conclude then by the Squeeze theorem that: $$\lim_{x\rightarrow 2}\sin^2(\pi x) = 0$$
05

State the final result

Now that we have obtained the limit, we can write the final answer: $$\lim _{x \rightarrow 2} \frac{x^{2}-4 x+4}{\sin ^{2}(\pi x)}=0$$

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A mass oscillates up and down on the end of a spring. Find its position \(s\) relative to the equilibrium position if its acceleration is \(a(t)=\sin (\pi t),\) and its initial velocity and position are \(v(0)=3\) and \(s(0)=0,\) respectively.

Consider the functions \(f(x)=\frac{1}{x^{2 n}+1},\) where \(n\) is a positive integer. a. Show that these functions are even. b. Show that the graphs of these functions intersect at the points \(\left(\pm 1, \frac{1}{2}\right),\) for all positive values of \(n\) c. Show that the inflection points of these functions occur at \(x=\pm \sqrt[2 n]{\frac{2 n-1}{2 n+1}},\) for all positive values of \(n\) d. Use a graphing utility to verify your conclusions. e. Describe how the inflection points and the shape of the graphs change as \(n\) increases.

Give an argument to support the claim that if a function is concave up at a point, then the tangent line at that point lies below the curve near that point.

Determine whether the following statements are true and give an explanation or counterexample. a. By l'Hôpital's Rule, \(\lim _{x \rightarrow 2} \frac{x-2}{x^{2}-1}=\lim _{x \rightarrow 2} \frac{1}{2 x}=\frac{1}{4}\) b. \(\lim _{x \rightarrow 0}(x \sin x)=\lim _{x \rightarrow 0} f(x) g(x)=\lim _{x \rightarrow 0} f^{\prime}(x) \lim _{x \rightarrow 0} g^{\prime}(x)=\) \(\left(\lim _{x \rightarrow 0} 1\right)\left(\lim _{x \rightarrow 0} \cos x\right)=1\) c. \(\lim _{x \rightarrow 0^{+}} x^{1 / x}\) is an indeterminate form. d. The number 1 raised to any fixed power is 1. Therefore, because \((1+x) \rightarrow 1\) as \(x \rightarrow 0,(1+x)^{1 / x} \rightarrow 1\) as \(x \rightarrow 0\) e. The functions \(\ln x^{100}\) and \(\ln x\) have comparable growth rates as \(x \rightarrow \infty\) f. The function \(e^{x}\) grows faster than \(2^{x}\) as \(x \rightarrow \infty\).

Show that any exponential function \(b^{x},\) for \(b>1,\) grows faster than \(x^{p},\) for \(p>0\).

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.