Question

If$x^2+1/x^2=38$then what is the value of |x-1/x|?

• A. 5
• B. 6
• C. 12
• D. 18

Answer 1

Answer:

B. 6

If $x^2+1/x^2=k$then, $x-1/x=\sqrt{k-2}$

So here,

$x^2+1/x^2=38$ then,

$x-1/x=\sqrt{38-2}=\sqrt{36}=6$