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If X²+ X + 1 =0 then the value of x ^3n is​

User Wellingr
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1 Answer

4 votes

Recall that


1-x^n=(1-x)(1+x+x^2+\cdots+x^(n-1))

So we have


x^2+x+1=0\implies(1-x^3)/(1-x)=0\implies x^3=1

Then for any
n, we have


x^(3n)=(x^3)^n=1^n=1

User Meliana
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