/*! 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 65 Find the intervals between \(-2 ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Find the intervals between \(-2 \pi\) and \(2 \pi\) on which the given function is (a) increasing or (b) decreasing. tangent

Short Answer

Expert verified
\(\tan(x)\) is increasing on \((-2\pi, -3\pi/2)\), \((-\pi/2, \pi/2)\), and \((\pi/2, 3\pi/2)\). It is never decreasing.

Step by step solution

01

Understand the Function Behavior

The function given is the tangent function. The tangent function, \(\tan(x)\), is periodic with a period of \(\pi\). This means that its behavior repeats every \(\pi\) units. Therefore, in the interval \([-2\pi, 2\pi]\), we need to analyze the behavior of \(\tan(x)\) between \(-\pi/2 + n\pi\) and \(\pi/2 + n\pi\) for \(n\) being an integer.
02

Determine Where Tangent Is Undefined

The tangent function is undefined where its cosine counterpart is zero. This occurs at \(x = -\pi/2 + n\pi\). In the interval \([-2\pi, 2\pi]\), these points are \(-3\pi/2, -\pi/2, \pi/2, 3\pi/2\). These points divide the interval into segments where the tangent function can be defined.
03

Identify Increasing Intervals

The derivative of \(\tan(x)\) is \(\sec^2(x)\), which is always positive wherever it is defined. This means \(\tan(x)\) is increasing wherever it exists between vertical asymptotes. Thus, \(\tan(x)\) is increasing on \((-2\pi, -3\pi/2)\), \((-\pi/2, \pi/2)\), and \((\pi/2, 3\pi/2)\) within the given interval.
04

Identify Decreasing Intervals

Because the tangent function's derivative, \(\sec^2(x)\), never becomes negative (it is always positive between asymptotes), there are no intervals where \(\tan(x)\) is decreasing within the given range of \([-2\pi, 2\pi]\).

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!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Periodic Behavior
The periodic behavior of a function refers to its ability to repeat values in regular cycles. For the tangent function, \( \tan(x) \), this period is \( \pi \). This means every \( \pi \) units, the tangent function repeats its pattern. Within the interval from \( -2\pi \) to \( 2\pi \), the behavior of the function resets sequentially with each period.

Understanding periodic behavior is crucial for functions like \( \tan(x) \) because it helps in predicting the function's values beyond initially observed intervals. When analyzing \( \tan(x) \) over a specified interval, remember it mimics its pattern at predictable intervals of \( \pi \). This repetitive nature aids in identifying function behaviors effectively within extended ranges.
Trigonometric Functions
Trigonometric functions, including sine, cosine, and tangent, are the cornerstone of trigonometry. They relate angles to ratios of sides in right triangles and can be understood in terms of the unit circle.

The tangent function, \( \tan(x) = \frac{\sin(x)}{\cos(x)} \), gives the ratio of sine to cosine. This function features special properties: it repeats its values every \( \pi \) degrees (or radians) and is undefined wherever the cosine function is zero. This characteristic results in vertical asymptotes where the tangent function values are theoretically infinite, occurring at odd multiples of \( \frac{\pi}{2} \), such as \( \frac{\pi}{2}, -\frac{\pi}{2} \), etc. These asymptotes are critical when exploring the function's domain.
Asymptote Behavior
Asymptotes describe the behavior of functions as they approach certain lines. For tangent, vertical asymptotes occur at points where the function is not defined due to the division by zero in its calculation.

In the case of \( \tan(x) \), these occur where \( \cos(x) = 0 \, \), translating to vertical asymptotes at points like \( -\frac{3\pi}{2}, -\frac{\pi}{2}, \frac{\pi}{2}, \) and \( \frac{3\pi}{2} \) within \( -2\pi <<< \leq 2\pi \). As the function approaches these asymptotes, its values grow larger in magnitude but never actually reach the line, illustrating their crucial role in understanding the tangent's behavior over specified intervals.
Interval Analysis
Interval analysis determines where certain properties of functions apply across specified ranges. In analyzing \( \tan(x) \) within \( [-2\pi, 2\pi] \, \), intervals are determined based on the location of its asymptotes.

- \( \tan(x) \) is defined and increasing in the intervals \( (-2\pi, -\frac{3\pi}{2}) \), \( (-\frac{\pi}{2}, \frac{\pi}{2}) \), and \( (\frac{\pi}{2}, \frac{3\pi}{2}) \). - The function shows an increasing pattern across any interval that doesn't contain its vertical asymptotes, supported by the positivity of its derivative \( \sec^2(x) \), which indicates upward trend without a decrease across its domain in \( [-2\pi, 2\pi] \).By dissecting these intervals, we determine the regions of increase critical for comprehending the function's full behavior over the specified range.

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

Use fundamental identities to find the values of the trigonometric functions for the given conditions. $$\cos \theta=\frac{1}{2} \text { and } \sin \theta<0$$

The formula specifles the position of a point \(P\) that is moving harmonically on a vertical axis, where \(t\) is in seconds and \(d\) is in centimeters. Determine the amplitude, period, and frequency, and describe the motion of the point during one complete oscillation (starting at \(t=0\) ). $$d=4 \cos \frac{3 \pi}{2} t$$

The formula specifles the position of a point \(P\) that is moving harmonically on a vertical axis, where \(t\) is in seconds and \(d\) is in centimeters. Determine the amplitude, period, and frequency, and describe the motion of the point during one complete oscillation (starting at \(t=0\) ). $$d=\frac{1}{3} \cos \frac{\pi}{4} t$$

\(A\) conveyor belt 9 meters long can be hydraulically rotated up to an angle of \(40^{\circ}\) to unload cargo from airplanes (see the figure). (a) Find, to the nearest degree, the angle through which the conveyor belt should be rotated up to reach a door that is 4 meters above the platform supporting the belt. (b) Approximate the maximum height above the platform that the belt can reach. (IMAGE CAN NOT COPY)

A ship leaves port at 1: 00 P.M. and sails in the direction \(\mathrm{N} 34^{\circ} \mathrm{W}\) at a rate of \(24 \mathrm{mi} / \mathrm{hr}\). Another ship leaves port at 1: 30 p.M. and sails in the direction \(N 56^{\circ} \mathrm{E}\) at a rate of \(18 \mathrm{mi} / \mathrm{hr}\) (a) Approximately how far apart are the ships at 3: 00 P.M.? (b) What is the bearing, to the nearest degree, from the first ship to the second?

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.