Math, asked by aakanksharanjan2006, 1 year ago

if x^3+1/x^3=2 find x+1/x

Answers

Answered by BrainlyPopularman
1

Answer:

 {(x +  \frac{1}{x}) }^{3}  =  {x}^{3}  +  \frac{1}{ {x}^{3} }  + 3(x +  \frac{1}{x} ) \\  \\ suppose \:  \: that \:  \: x +  \frac{1}{x}  = t \\  \\  {t}^{3}  = 2 + 3t \\  \\ t = 2 \:  \: \: and \:  \: t =  - 1 \\  \\ x +  \frac{1}{x}  = 2 \\ x = 2 \\  \\  \\ x +  \frac{1}{x}  =  - 1 \\  {x}^{2}  + x + 1 = 0(no \: solution) \\  \\  \\  \\ x = 2

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