There are six different sixth roots of 64. That is, there are six complex numbers that solve x^6=0, find them.
I think you meant x^6=64, nbot x^6=0... Here you go!
The obvious two solutions to this equation is 2 and -2 since, (±2)6 = 64 but the question asked for the complex numbers too, so there are more solutions.
The first step in order to approach this problem is to factor x6 = 64.
We can re-write this problem into x6 - 26 = 0
And also, (x3)2-(23)2=0
After using difference of cubes and sum of cubes(search it up if you don't know what it is)
I got: (x-2)(x^2+2x+2^2)*{(x+2)(x^2-2x+2^2)}=0
We need to solve ±(x-2)=0,
(x^2+2x+2^2)=0
(x^2-2x+2^2)=0
After you do, you have your six conjugates. I'll leave the solving for you!
64^(1/6) =
+ OR - 2
2 e^((i π)/3)≈1.0000 + 1.7321 i
2 e2 e^(-(2 i π)/3)≈-1.0000 + 1.7321 i
2 e^(-(2 i π)/3)≈-1.0000 - 1.7321 i
2 e^(-(i π)/3)≈1.0000 - 1.7321 i
Thank you supermanaccz and guest,
Superman, I have never seen it done your way, there are usually several ways to solve the same problem and it is interesting to see alternate routes. ![]()
There are six different sixth roots of 64. That is, there are six complex numbers that solve x^6=0, find them.
The 6 points will be equally distributed on the complex plane at an absolute distance of 2 units.
A revolution is 2pi radians so the points will be 2pi/6 = pi/3 radians apart.
Also you know that one of them is \(2 = 2e^0 = 2e^{(0\pi/3)i}\)
so here are your roots.
\(\sqrt[6]{2}=2e^{(0\pi/3)i}, \quad2 e^{1(\pi/3)i}, \quad2 e^{2(\pi/3)i}, \quad2 e^{3(\pi/3)i},\ \quad2 e^{4(\pi/3)i}, \quad2 e^{5(\pi/3)i}\\ \sqrt[6]{2}=2e^{(\pi/3)i}, \quad2 e^{(\pi/3)i}, \quad2 e^{(2\pi/3)i}, \quad2 e^{\pi i},\ \quad2 e^{(4\pi/3)i}, \quad2 e^{(5\pi/3)i}\\\)
I've done it exactly the same way as our guest only he/she has gone from -pi to +pi and I have gone from 0 to 2pi. I am not sure if there is any convention on this, but the answers are the same.