Question

Calculati x²+1/x²,stiind can x-1/x=3

Answer 1

(x-1/x)^2=3^2 x^2-2x1/x+1/x^2=9|-2x1/x x^2+1/x^2=7

Answer 2

rezolvam intai a doua ecuatia x-1/x=3
3x=x-1
2x=-1
x=-1/2
$x^{2} + \frac{1}{ x^{2} } = \frac{1}{4} + \frac{1}{ \frac{1}{4} } = \frac{1}{4} +4$= $\frac{17}{4}$