👤

Sa se calculeze x² + [tex]\frac{1}{x ^{2} } [/tex] , stiind ca x- [tex] \frac{1}{x} [/tex] = 6


Răspuns :

Ridicam la patrat ecuatia data:

[tex]\left(x-\dfrac1x\right)^2=6 ^2\Rightarrow x^2-2\cdot x\cdot\dfrac1x+\dfrac{1}{x^2}=36\Rightarrow x^2+\dfrac{1}{x^2}=38[/tex]