How to Calculate the Complex Roots of x^5 = 10?

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To calculate the complex roots of x^5 = 10, the real root is identified as approximately 1.858. The method involves transforming the equation into z^5 = 1 and multiplying the solutions by the fifth root of 10. Newton's method is not suitable for finding complex roots; instead, polar representation of complex numbers should be utilized. The polar form of 10 can be expressed as 10e^(iθ), where θ represents multiples of 2π. Understanding Argand diagrams can aid in visualizing these complex solutions.
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Homework Statement
Given x^5=10, find the five roots and plot them on an Argand diagram.
Relevant Equations
Newton's method.
Mentor note: Member reminded that some effort must be shown.
Real root is 1.858.
Just don't know which method to use to find the 4 complex roots
 
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x^5=10
(\frac{x}{\sqrt[5]{10}})^5=z^5=1

So get solutions of ##z^5=1## and multiply them with ##\sqrt[5]{10}##.
 
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Newton's method will only find the real solutions. With complex numbers, you should consider the properties of complex numbers to get the other, complex solutions. Even for the real solution, they probably don't want you to use Newton's method, but rather just leave that solution as ##10^{1/5}##.
For the complex solutions, do you know about the representation of a complex number in its polar form (##re^{i\theta}##)? If so, consider 10 in its polar form: ##10e^{i0} = 10e^{i2\pi}= 10e^{i4\pi}= 10e^{i6\pi}= 10e^{i8\pi}= 10e^{i10\pi}##. Now take the fifth root of the individual factors, 10 and ##e^{i2n\pi}##
 
mardybum9182 said:
Just don't know which method to use to find the 4 complex roots

Do you know what an Argand diagram is?
 
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