Find the root of the complex 3+4i
What we should know is that the root 3+4i is a complex number that looks alot like a+bi.
We can say : rt(3+4i) = a+bi (Where we dont know what a & b is..yet)
and when we square both sides (rt(3+4i))^2=(a+bi)^2 | 3+4i = (a+bi)^2
we get 3+4i = a^2+2abi-b^2
We seperate the Real and Imaginary parts to get a simultainus equation
3 = a^2-b^2
4 = 2ba
if this is solved we get a= (+-)2 and b =(+-)1
to get (+-)(2+i) <--- which is the answer
AA
Answered by Ade A. • Further Mathematics tutor
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