Răspuns :
x + 1/x = V11 Ridici toata ecuatia la puterea a 2
(x+ 1/x)² = (V11)²
x² + 2x*1/x + (1/x)² = 11
x² + 2 + 1/x² = 11
x² + 1/x² = 11-2
x² + 1/x² = 9
x + 1/x = V11 Ridici toata ecuatia la puterea a 2
(x+ 1/x)² = (V11)²
x² + 2x*1/x + (1/x)² = 11
x² + 2 + 1/x² = 11
x² + 1/x² = 11-2
x² + 1/x² = 9