Wednesday, 16 December 2015

complex numbers - How to solve 2sqrt3i+z3=0?




I have tried to solve this "problem" so that i have z switched with a+bi. Then after some hours of solving this riddle i have gain an enormous numbers of lines but with no solution.



23i+z3=0



z=a+bi



I want to know how much is a and b.


Answer



z3=2+3i




Let's express 2+3i in form of r(cosθ+isinθ)



r=4+3=7



θ=arctan(32)+π



so we may write that:



z3=7(cosθ+isinθ)




Now if you apply following formula you can calculate a and b:



z=37(cos(θ+2kπ3)+isin(θ+2kπ3)) ,where kZ



so: a=37cos(θ+2kπ3) and b=37sin(θ+2kπ3)


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