Converting to Polar and Cartesian form

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Homework Help Overview

The discussion revolves around converting complex numbers to Cartesian and polar forms. The original poster expresses confusion regarding the process of expressing the given complex numbers in these forms, specifically mentioning examples involving division and square roots of complex numbers.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants inquire about the original poster's understanding of polar and Cartesian forms, as well as the concepts of real and imaginary parts, modulus, and argument of complex numbers. There are suggestions to rationalize the denominator and to clarify whether the numbers in question are complex numbers or vector components.

Discussion Status

The discussion is ongoing, with some participants providing guidance on concepts related to complex numbers and rationalizing denominators. There is a lack of explicit consensus, as participants explore different interpretations and approaches to the problem.

Contextual Notes

There is a note regarding the original poster's lack of effort in the initial post, which may affect the direction of the discussion. Additionally, participants mention the importance of understanding foundational concepts before proceeding with the problem.

SteliosVas
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Mod note: This post with template not used and no effort shown received a warning.

Okay I am totally confused in this.
This is not a homework question but rather one I saw online and was wondering for example how to solve it

The question was -3-i/-8+6i to be expressed into Cartesian form.

Another similar one was -2-2*sqrt(3i) into polar form.

How can I do this?

Can someone actually explain I don't get it fully. I know you usually use Cartesian form but yeah...
 
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Do you know what polar and cartesian forms are?
Do you know how to find the real and imaginary parts of a complex number?
Do you know how to find the modulus and argument of a complex number?
If the answer to any of the above is "no", then please look them up before returning.
If the answer to all of the above is "yes", then what's the problem?
Please show your best attempt.

Note:
1. search for: "rationalize the denominator"
2. search for: "square root of pi"
 
Are these complex numbers or vector components. When you have an i in the denominator, you may treat it as i^-1 which equals i which will help eliminating complex numbers. If it is a vector component, recall x=rcostheta y=rsintheta.
 
JohnPrior3 said:
Are these complex numbers or vector components.
It's fairly obvious that they are complex numbers.
JohnPrior3 said:
When you have an i in the denominator, you may treat it as i^-1 which equals i which will help eliminating complex numbers.
This doesn't help if the denominator has a sum of terms in it.
JohnPrior3 said:
If it is a vector component, recall x=rcostheta y=rsintheta.
 
you may treat it as i^-1 which equals i
... misplaced a minus sign I think, typo?
Just so people who google here don't get the wrong idea:$$\frac{1}{\sqrt{-1}}=\frac{1}{i}=-i$$ ... it's actually easier to use in the fraction form.

The trick: Since I can multiply by 1 without changing the number, and any number divided by itself is 1, I can do: $$\frac{1}{i} = \frac{i}{i}\frac{1}{i} = \frac{i}{-1} = -i$$ ... see what I did there?

The general form of this trick, when it leaves a real number in the denominator, is called "rationalizing the denominator" (see note post #2).
Hopefully OP will get back to us and supply the needed information.
 

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