/*! 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 55 Evaluate the integrals. $$\int... [FREE SOLUTION] | 91Ó°ÊÓ

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Evaluate the integrals. $$\int_{\pi / 4}^{\pi / 4} \cosh (\tan \theta) \sec ^{2} \theta d \theta$$

Short Answer

Expert verified
The integral evaluates to 0.

Step by step solution

01

Recognize the structure of the integral

The given integral is \( \int_{\pi / 4}^{\pi / 4} \cosh (\tan \theta) \sec ^{2} \theta \, d \theta \). An important observation is that the limits of integration are the same: from \( \pi/4 \) to \( \pi/4 \).
02

Evaluate using the limits

When the upper and lower limits of a definite integral are the same, the integral evaluates to zero, regardless of the integrand. This is because the definite integral represents the area under the curve, and if there is no interval (difference in limits), there is no area to compute.
03

Express the result

Accordingly, we conclude that \( \int_{\pi / 4}^{\pi / 4} \cosh (\tan \theta) \sec ^{2} \theta \, d \theta = 0 \).

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Key Concepts

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

Demystifying Calculus
Calculus is a branch of mathematics that studies continuous change. Its two main areas are differentiation and integration. Differentiation refers to how functions change, while integration involves summing up small parts to find wholes, like areas. Calculus is fundamental to understanding the behavior of functions and their graphs.

In the context of this exercise, we're dealing with definite integrals, which focus on finding the total area under a curve within a specific interval. Calculus gives us the tools to express this area in terms of functions and limits. It’s like summing up infinitely small parts to understand a whole picture. This can be practical to calculate quantities like displacement, area, volume, and other cumulative measures.
  • Differentiation - finding rates of change
  • Integration - accumulating values over an interval
  • Applications - physics, engineering, economics
Understanding Integral Properties
Integral properties are rules that make working with integrals more manageable. One key property of definite integrals is that if the upper and lower limits of integration are the same, the integral evaluates to zero. This integral, \(\int_{a}^{a} f(x) dx \), is zero because there’s no interval to measure, hence no area.

Other essential properties include:
  • Linearity: \(\int_{a}^{b} [cf(x) + g(x)] dx = c\int_{a}^{b} f(x) dx + \int_{a}^{b} g(x) dx\)
  • Reversal of limits: \(\int_{a}^{b} f(x) dx = -\int_{b}^{a} f(x) dx\)
  • Additivity: \(\int_{a}^{c} f(x) dx + \int_{c}^{b} f(x) dx = \int_{a}^{b} f(x) dx\)
Knowing these properties allows us to simplify and evaluate integrals without always computing them from scratch. It's about recognizing patterns and streamlining our approach, saving time and effort, especially in complex calculations.
Relating to Area Under the Curve
The concept of the area under a curve is fundamental to understanding definite integrals. A definite integral calculates the net area between the curve of a function and the x-axis over a specified interval. This area can sometimes be negative if the function is below the x-axis.

In this specific exercise, the integral \(\int_{ rac{\pi}{4}}^{ rac{\pi}{4}} \cosh( an \theta) \, \sec^2 \theta \ d\theta\)evaluates to zero. This result occurs because there is no interval between the lower and upper limits; hence, the area is nonexistent. Understanding this concept is crucial because it involves recognizing that the 'area' represented by the integral depends entirely on the span of the limits and the behavior of the function within those limits.
  • The integral finds the net signed area between a function and the x-axis
  • Zero area if limits are the same or if function crosses evenly
  • Interprets physical quantities like distance or total change

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Most popular questions from this chapter

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