Question

The length of the semi-transverse axis of the rectangular hyperbola $xy=8$ is

• A. $2$
• B. $4$
• C. $16$
• D. $8$

Answer 1

The correct option is B $4$

For a rectangular hyperbola $xy=c^2$, the semi-transverse axis is $\sqrt{2}c$

Here, $c=\sqrt{8}$

$\therefore$ semi-transverse axis becomes $\sqrt{2}\times \sqrt{8}=\sqrt{16}=4$