Question

$daca \: x + \frac{1}{x} =7 calculati \: \: \: {x}^{2} + \frac{1}{ {x}^{2} }$
am nevoie urgent!​

Answer 1

x+1/x = 7 ridici toata ecuatia la a 2-a

(x+1/x)² = 7²

x²+ 2x×1/x + 1/x² = 49

x²+2 +1/x² = 49

x² + 1/x² = 47

Answer 2

Răspuns:

(x+1/x)²=x²+1/x²+2=49 ;   x²+1/x²=49-2=45

Explicație pas cu pas: