How Do You Calculate Cube Roots of Complex Numbers in Modulus Argument Form?

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To calculate the cube roots of the complex number (3 - i)/(3 + i) in modulus-argument form, first simplify the fraction to express it in the form a + bi. Next, convert this result into polar form using r(cosθ + i sinθ). Apply DeMoivre's Theorem to find the cube roots, which involves taking the cube root of the modulus and dividing the argument by three. Additionally, it's important to show your attempts at solving the problem to receive further assistance. This process will lead to the principal root expressed in the desired format.
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can someone help me solve this question as fasd as possible??
im really headache wif it...
thx~~

determine the 3 cube roots of 3-i over 3+i giving the result in modulus argument form,express the principal root in the form a+Jb
 
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hello..anyone can help me out??
 
whooi said:
can someone help me solve this question as fasd as possible??
im really headache wif it...
thx~~

determine the 3 cube roots of 3-i over 3+i giving the result in modulus argument form,express the principal root in the form a+Jb

Do not bump your post after only 16 minutes. It is unreasonable to expect fast help all the time here on the PF.

Also, you must show your attempt at a solution before we can be of help. Show us how you would go about simplifying the complex fraction that you are describing...
 
First off, you're going to want to calculate (3 - i)/(3 + i), to get it in the form a + bi. After that, you should calculate the polar form of this complex number, r(cos\theta + i sin\theta). After that, you can use DeMoivre's Formula to find a cube root, which says that
(r(cos\theta + i sin\theta))^{1/n} = r^{1/n}(cos(\theta/n) + i sin(\theta/n)).
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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