Question

Eccentricity of the curve $x^2-y^2=a^2$ is equal to

• A. $2$
• B. $\sqrt{2}$
• C. $4$
• D. None of these

Answer 1

Answer: (B)

Given equation of curve can be rewritten as
$\frac{x^2}{a^2}-\frac{y^2}{a^2}=1$
$\therefore$ $e=\sqrt{1+\frac{b^2}{a^2}}=\sqrt{1+\frac{a^2}{a^2}}$
$\Rightarrow$ $e=\sqrt{2}$