Question

Відомо,що x^2 +9/x^2=10,знайдіть значення виразу x+3/x

Answer 1

(x - 3/x)^2 = x^2 - 2*x*3/x + 9/x^2 = x^2 + 9/x^2 - 6

x^2 + 9/x^2 = 55

x^2 + 9/x^2 - 6 = 49

(x - 3/x)^2 = 49

x - 3/x = 7

x - 3/x = -7

Answer 2

$x - \frac{3}{x} = б2$

Объяснение:

$(x - \frac{3}{x})^2 = x^2 - 2*x*\frac{3}{x} + \frac{9}{x^2} = x^2 - 6 + \frac{9}{x^2}\\\\x^2 + \frac{9}{x^2} = 10\\\\x^2 + \frac{9}{x^2} = 4 + 6\\\\x^2 -6 + \frac{9}{x^2} = 4\\\\(x - \frac{3}{x})^2 = 4\\\\x - \frac{3}{x} =б\sqrt{4}\\\\ x - \frac{3}{x} = б2$