A:If x2+x+1=0,then value of (x+\frac{1}{x})^{2}+(x^{2}+\frac{1}{x^{2}})^{2}+......+(x^{21}+\frac{1}{x^{21}})^{2}
is 42
R:ω,ω2 are roots given by equation x+\frac{1}{x}=-1,x^{3}+\frac{1}{x^{3}}=2
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3 Answers
62roots are ω and ω2
so all these terms x+1/x
x2+1/x2 etc are -1!
this sum willl give
(1+1+4)+(1+1+4)... 7 times
whihc is 42
reasoning is also correct!
24ya sir i was also getting a ......wanted to confirm it .........thanx for help.....[1]