question on complex number (1 Viewer)

[Mainoyi]

w=-1+√3 i

show w is a root of z^3-8=0

 

[untouchablecuz]

enjoy

 

[Mainoyi]

enjoy

thanks heaps..!

 

[addikaye03]

w=-1+√3 i

show w is a root of z^3-8=0

It would be just as easy to find all the roots of z^3-8=0, since it factorises nicely.

(z-2)(z^2+2z+4)=0

z=2 and z^2+2z+4=0

(z+1)^2-3i^2=0

(z+1)-√3i=0 and z+1+√3i=0

therefore z=2, -1-√3 and w where w=-1+√3 i

But untouchablecuz's method is better for most Q since its more of a generalised method.