Cube roots of 8?
8 traditionally has 1 cube root. 2. This is only the real root. It has 2 more complex roots!How can we see this?Consider a vector on the argand diagram. If we square it. What happens to it's magnitude and arguement?So as we can see. If 8 is expressed on an argand diagram. The vector at 2 when cubed maps to 8. But can you see the two other points?In general the nth cube root of a complex number has n roots.
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Answered by Vishal J. • Further Mathematics tutor
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