/*! 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} Q. 25 In Exercises 17-25 find a defini... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

In Exercises 17-25 find a definite integral expression that represents the area of the given region in the polar plane, and then find the exact value of the expression.

The graph of the polar equation r=secθ-2cosθforθ∈-π2,π2 is called a strophoid. Graph the strophoid and find the area bounded by the loop of the graph.

Short Answer

Expert verified

Ans: The area of the equation isA=2-Ï€2

Step by step solution

01

Step 1. Given information: 

The polar equation r=secθ-2cosθ

02

Step 2. Implying formula: 

Formula to find the area is A=∫αβ12(f(θ))2dθor A=∫αβ12r2dθ.

By equating, secθ-2cosθ=0

Thus,

secθ=2cosθcosθ=12cosθ=cosπ4θ=π4

The limits are from 0 to π4.

03

Step 3. Continue:

Then,

A=2·12∫0π4(secθ-2cosθ)2dθA=∫0π4sec2θ+4cos2θ-2·2secθ·cosθdθA=∫0π4sec2θ+4cos2θ-4dθ

04

Step 4. Simplification:

A=∫0π4sec2θ+41+cos2θ2-4dsincecos2θ=1+cos2θ2A=∫0π4sec2θ+2+2cos2θ-4dθA=(tanθ-2θ+sin2θ)0π4
05

Step 5. Continue:

Thus,

A=tanπ4-2·π4+sin2·π4A=1-π2+1A=2-π2

Therefore, the area of the equation is A=2-Ï€2.

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

Study anywhere. Anytime. Across all devices.