Question no. 6

Question no. 6 e of 3 then 0 and are the complex cube roots Of unity. show that S) If and 13 are the complex cube roots of unity, show that -113-1 = o. 6) If x=a+b, y=åa-+ßb and z=aß+bu where and ß are complex cube roots of unity, show that .0z=a3+b3- 7) If w is the complex cube-root of unity, show that 8) If w is the complex cube-root of unity, show that _ 9) If w denotes the complex cube root of unity, prove the following Im vv is the comolex cube root of unity then prove

Dear student
We have, x=a+b,y=αa+βb,z=αb+βa Now, as α,β are complex cube root of unity so we have, αβ=1,1+α+β=0,α2=β,β2=αso xyz= (a+b)(αa+βb)(αb+βa)=(a+b)(abα2+a2αβ+b2αβ+abβ2)=(a+b)(a2+b2+ab(α2+β2))=(a+b)(a2+b2+ab(α+β))=(a+b)(a2+b2+ab(-1))=(a+b)(a2+b2-ab)=a3+b3
Hope this clears your doubt 
With regards 

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