Find polar forms for zw, z/w, and 1/z by first putting z and w into polar form. $ z=2sqrt{3}-2i, w=-1+i $












0












$begingroup$


I already figured out the answer to the first part zw but the rest is confusing me










share|cite|improve this question









$endgroup$












  • $begingroup$
    Welcome to Maths SX! And what did you obtain?
    $endgroup$
    – Bernard
    Dec 9 '18 at 21:36










  • $begingroup$
    How did you "figure out the answer to the first part?" The other parts should not be a challenge.
    $endgroup$
    – Mark Viola
    Dec 9 '18 at 21:36










  • $begingroup$
    well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:44












  • $begingroup$
    I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:46
















0












$begingroup$


I already figured out the answer to the first part zw but the rest is confusing me










share|cite|improve this question









$endgroup$












  • $begingroup$
    Welcome to Maths SX! And what did you obtain?
    $endgroup$
    – Bernard
    Dec 9 '18 at 21:36










  • $begingroup$
    How did you "figure out the answer to the first part?" The other parts should not be a challenge.
    $endgroup$
    – Mark Viola
    Dec 9 '18 at 21:36










  • $begingroup$
    well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:44












  • $begingroup$
    I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:46














0












0








0





$begingroup$


I already figured out the answer to the first part zw but the rest is confusing me










share|cite|improve this question









$endgroup$




I already figured out the answer to the first part zw but the rest is confusing me







calculus






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Dec 9 '18 at 21:33









mysticemmamysticemma

1




1












  • $begingroup$
    Welcome to Maths SX! And what did you obtain?
    $endgroup$
    – Bernard
    Dec 9 '18 at 21:36










  • $begingroup$
    How did you "figure out the answer to the first part?" The other parts should not be a challenge.
    $endgroup$
    – Mark Viola
    Dec 9 '18 at 21:36










  • $begingroup$
    well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:44












  • $begingroup$
    I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:46


















  • $begingroup$
    Welcome to Maths SX! And what did you obtain?
    $endgroup$
    – Bernard
    Dec 9 '18 at 21:36










  • $begingroup$
    How did you "figure out the answer to the first part?" The other parts should not be a challenge.
    $endgroup$
    – Mark Viola
    Dec 9 '18 at 21:36










  • $begingroup$
    well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:44












  • $begingroup$
    I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
    $endgroup$
    – mysticemma
    Dec 9 '18 at 21:46
















$begingroup$
Welcome to Maths SX! And what did you obtain?
$endgroup$
– Bernard
Dec 9 '18 at 21:36




$begingroup$
Welcome to Maths SX! And what did you obtain?
$endgroup$
– Bernard
Dec 9 '18 at 21:36












$begingroup$
How did you "figure out the answer to the first part?" The other parts should not be a challenge.
$endgroup$
– Mark Viola
Dec 9 '18 at 21:36




$begingroup$
How did you "figure out the answer to the first part?" The other parts should not be a challenge.
$endgroup$
– Mark Viola
Dec 9 '18 at 21:36












$begingroup$
well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
$endgroup$
– mysticemma
Dec 9 '18 at 21:44






$begingroup$
well I ended up getting 4sqrt2(cos(7pi/4)+isin(7pi/4)) by multiplying the two roots together and then adding the two angles in radians but I can't seem to calculate the answer for the other two because I'm not sure how those rules must translate. I just needed some help with that
$endgroup$
– mysticemma
Dec 9 '18 at 21:44














$begingroup$
I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
$endgroup$
– mysticemma
Dec 9 '18 at 21:46




$begingroup$
I've also been stuck on this for like 2hrs now but I must be missing something major I would like to know how to do this easily and efficiently
$endgroup$
– mysticemma
Dec 9 '18 at 21:46










2 Answers
2






active

oldest

votes


















1












$begingroup$

https://en.wikipedia.org/wiki/Complex_number#Polar_form . Look at this page.



You need to calculate the norm and the angument to get the polar form of $z$ and $w$, and then do the operations that you want.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
    $endgroup$
    – Gil Astudillo
    Dec 10 '18 at 10:52





















1












$begingroup$

Hint



$z=r_1e^{itheta_1}, w=r_2e^{itheta_2}\z/w=(frac{r_1}{r_2})cdot e^{i({theta_1-theta_2})}=r'e^{ialpha}\1/z=(frac1{r_1}).e^{i(-theta_1)}=r''e^{ibeta}$



You need to take care that $alpha,beta$ lie in the domain of the principal argument.



Edit



One way to write the polar form of a complex number $z$ is $|z|(cos Arg(z)+isin Arg(z))$, while another way to write this is $|z|e^{iArg(z)}$, where $|z|$ denotes the amplitude of $z$ and $Arg(z)$ its principal argument. This is because $e^{iArg(z)}=cos Arg(z)+isin Arg(z)$, which comes from the Euler's formula.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
    $endgroup$
    – mysticemma
    Dec 9 '18 at 22:00












  • $begingroup$
    $z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:04












  • $begingroup$
    I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:17











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3033051%2ffind-polar-forms-for-zw-z-w-and-1-z-by-first-putting-z-and-w-into-polar-form%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









1












$begingroup$

https://en.wikipedia.org/wiki/Complex_number#Polar_form . Look at this page.



You need to calculate the norm and the angument to get the polar form of $z$ and $w$, and then do the operations that you want.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
    $endgroup$
    – Gil Astudillo
    Dec 10 '18 at 10:52


















1












$begingroup$

https://en.wikipedia.org/wiki/Complex_number#Polar_form . Look at this page.



You need to calculate the norm and the angument to get the polar form of $z$ and $w$, and then do the operations that you want.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
    $endgroup$
    – Gil Astudillo
    Dec 10 '18 at 10:52
















1












1








1





$begingroup$

https://en.wikipedia.org/wiki/Complex_number#Polar_form . Look at this page.



You need to calculate the norm and the angument to get the polar form of $z$ and $w$, and then do the operations that you want.






share|cite|improve this answer









$endgroup$



https://en.wikipedia.org/wiki/Complex_number#Polar_form . Look at this page.



You need to calculate the norm and the angument to get the polar form of $z$ and $w$, and then do the operations that you want.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Dec 9 '18 at 21:47









Gil AstudilloGil Astudillo

315




315












  • $begingroup$
    youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
    $endgroup$
    – Gil Astudillo
    Dec 10 '18 at 10:52




















  • $begingroup$
    youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
    $endgroup$
    – Gil Astudillo
    Dec 10 '18 at 10:52


















$begingroup$
youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
$endgroup$
– Gil Astudillo
Dec 10 '18 at 10:52






$begingroup$
youtube.com/watch?v=wlcDS7SKmj8 . There you have it, step by step.
$endgroup$
– Gil Astudillo
Dec 10 '18 at 10:52













1












$begingroup$

Hint



$z=r_1e^{itheta_1}, w=r_2e^{itheta_2}\z/w=(frac{r_1}{r_2})cdot e^{i({theta_1-theta_2})}=r'e^{ialpha}\1/z=(frac1{r_1}).e^{i(-theta_1)}=r''e^{ibeta}$



You need to take care that $alpha,beta$ lie in the domain of the principal argument.



Edit



One way to write the polar form of a complex number $z$ is $|z|(cos Arg(z)+isin Arg(z))$, while another way to write this is $|z|e^{iArg(z)}$, where $|z|$ denotes the amplitude of $z$ and $Arg(z)$ its principal argument. This is because $e^{iArg(z)}=cos Arg(z)+isin Arg(z)$, which comes from the Euler's formula.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
    $endgroup$
    – mysticemma
    Dec 9 '18 at 22:00












  • $begingroup$
    $z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:04












  • $begingroup$
    I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:17
















1












$begingroup$

Hint



$z=r_1e^{itheta_1}, w=r_2e^{itheta_2}\z/w=(frac{r_1}{r_2})cdot e^{i({theta_1-theta_2})}=r'e^{ialpha}\1/z=(frac1{r_1}).e^{i(-theta_1)}=r''e^{ibeta}$



You need to take care that $alpha,beta$ lie in the domain of the principal argument.



Edit



One way to write the polar form of a complex number $z$ is $|z|(cos Arg(z)+isin Arg(z))$, while another way to write this is $|z|e^{iArg(z)}$, where $|z|$ denotes the amplitude of $z$ and $Arg(z)$ its principal argument. This is because $e^{iArg(z)}=cos Arg(z)+isin Arg(z)$, which comes from the Euler's formula.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
    $endgroup$
    – mysticemma
    Dec 9 '18 at 22:00












  • $begingroup$
    $z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:04












  • $begingroup$
    I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:17














1












1








1





$begingroup$

Hint



$z=r_1e^{itheta_1}, w=r_2e^{itheta_2}\z/w=(frac{r_1}{r_2})cdot e^{i({theta_1-theta_2})}=r'e^{ialpha}\1/z=(frac1{r_1}).e^{i(-theta_1)}=r''e^{ibeta}$



You need to take care that $alpha,beta$ lie in the domain of the principal argument.



Edit



One way to write the polar form of a complex number $z$ is $|z|(cos Arg(z)+isin Arg(z))$, while another way to write this is $|z|e^{iArg(z)}$, where $|z|$ denotes the amplitude of $z$ and $Arg(z)$ its principal argument. This is because $e^{iArg(z)}=cos Arg(z)+isin Arg(z)$, which comes from the Euler's formula.






share|cite|improve this answer











$endgroup$



Hint



$z=r_1e^{itheta_1}, w=r_2e^{itheta_2}\z/w=(frac{r_1}{r_2})cdot e^{i({theta_1-theta_2})}=r'e^{ialpha}\1/z=(frac1{r_1}).e^{i(-theta_1)}=r''e^{ibeta}$



You need to take care that $alpha,beta$ lie in the domain of the principal argument.



Edit



One way to write the polar form of a complex number $z$ is $|z|(cos Arg(z)+isin Arg(z))$, while another way to write this is $|z|e^{iArg(z)}$, where $|z|$ denotes the amplitude of $z$ and $Arg(z)$ its principal argument. This is because $e^{iArg(z)}=cos Arg(z)+isin Arg(z)$, which comes from the Euler's formula.







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited Dec 9 '18 at 22:15

























answered Dec 9 '18 at 21:42









Shubham JohriShubham Johri

5,192717




5,192717












  • $begingroup$
    How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
    $endgroup$
    – mysticemma
    Dec 9 '18 at 22:00












  • $begingroup$
    $z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:04












  • $begingroup$
    I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:17


















  • $begingroup$
    How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
    $endgroup$
    – mysticemma
    Dec 9 '18 at 22:00












  • $begingroup$
    $z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:04












  • $begingroup$
    I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
    $endgroup$
    – Shubham Johri
    Dec 9 '18 at 22:17
















$begingroup$
How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
$endgroup$
– mysticemma
Dec 9 '18 at 22:00






$begingroup$
How do you obtain the reciprocal of z in trigonometric form? I have the second part I believe in trigonometric form now, as 2sqrt2(cos(13pi/12)+isin(13pi/6)).
$endgroup$
– mysticemma
Dec 9 '18 at 22:00














$begingroup$
$z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
$endgroup$
– Shubham Johri
Dec 9 '18 at 22:04






$begingroup$
$z=r_1e^{itheta_1}implies 1/z=frac1{r_1e^{itheta_1}}=frac1{r_1}cdot e^{i(-theta_1)}=r''e^{ibeta}=r''(cosbeta+isinbeta)$ (Euler's formula) where $r''=frac1{r_1}, beta=-theta_1$. Check whether $beta$ is in the domain of principal argument.
$endgroup$
– Shubham Johri
Dec 9 '18 at 22:04














$begingroup$
I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
$endgroup$
– Shubham Johri
Dec 9 '18 at 22:17




$begingroup$
I have edited the answer to include a little introduction to the Euler's Formula. Please refer to the link.
$endgroup$
– Shubham Johri
Dec 9 '18 at 22:17


















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3033051%2ffind-polar-forms-for-zw-z-w-and-1-z-by-first-putting-z-and-w-into-polar-form%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Plaza Victoria

In PowerPoint, is there a keyboard shortcut for bulleted / numbered list?

How to put 3 figures in Latex with 2 figures side by side and 1 below these side by side images but in...