Question
If in a hyperbola the eccentricity is $$\sqrt 3 ,$$ and the distance between the foci is 9 then the equation of the hyperbola in the standard form is :
A.
$$\frac{{{x^2}}}{{{{\left( {\frac{{\sqrt 3 }}{2}} \right)}^2}}} - \frac{{{y^2}}}{{{{\left( {\sqrt {\frac{3}{2}} } \right)}^2}}} = 1$$
B.
$$\frac{{{x^2}}}{{{{\left( {\frac{{3\sqrt 3 }}{2}} \right)}^2}}} - \frac{{{y^2}}}{{{{\left( {\frac{{3\sqrt 3 }}{2}} \right)}^2}}} = 1$$
C.
$$\frac{{{x^2}}}{{{{\left( {\frac{{3\sqrt 3 }}{2}} \right)}^2}}} - \frac{{{y^2}}}{{{{\left( {\frac{{3\sqrt 2 }}{2}} \right)}^2}}} = 1$$
D.
none of these
Answer :
$$\frac{{{x^2}}}{{{{\left( {\frac{{3\sqrt 3 }}{2}} \right)}^2}}} - \frac{{{y^2}}}{{{{\left( {\frac{{3\sqrt 3 }}{2}} \right)}^2}}} = 1$$
Solution :
For rectangular hyperbola, $$e = \sqrt 2 .$$ So, $${\left( {x - 1} \right)^2} + {\left( {y - 2} \right)^2} = {\left( {\sqrt 2 .\frac{{x + y - 1}}{{\sqrt 2 }}} \right)^2}.$$