/*! 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 19 Express the following polar coor... [FREE SOLUTION] | 91Ó°ÊÓ

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Express the following polar coordinates in Cartesian coordinates. $$\left(-4, \frac{3 \pi}{4}\right)$$

Short Answer

Expert verified
Question: Convert the polar coordinates \(\left(-4, \frac{3 \pi}{4}\right)\) to Cartesian coordinates. Answer: \(\left( 2\sqrt{2}, -2\sqrt{2} \right)\)

Step by step solution

01

Identify the given polar coordinates

We are given $$\left(-4, \frac{3 \pi}{4}\right),$$ where \(r = -4\) and \(\theta = \frac{3 \pi}{4}\).
02

Convert the polar coordinates to Cartesian coordinates

Use the equations for converting polar to Cartesian coordinates: $$ x = r \cos \theta = -4 \cos \frac{3 \pi}{4} $$ $$ y = r \sin \theta = -4 \sin \frac{3 \pi}{4} $$
03

Calculate the Cartesian coordinates

Find the cosine and sine values and multiply by \(r\): $$ x = -4 \left( -\frac{1}{\sqrt{2}} \right) = \frac{4}{\sqrt{2}} $$ $$ y = -4 \left( \frac{1}{\sqrt{2}} \right) = -\frac{4}{\sqrt{2}} $$
04

Simplify the Cartesian coordinates

To simplify the Cartesian coordinates, multiply the numerator and denominator by \(\sqrt{2}\) to rationalize the denominator: $$ x = \frac{4}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = 2\sqrt{2} $$ $$ y = -\frac{4}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = -2\sqrt{2} $$
05

Write the final answer in Cartesian coordinates

The Cartesian coordinates are: $$ \left( 2\sqrt{2}, -2\sqrt{2} \right) $$

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