UPSC NDA Math Model Paper 4

Given: Equation of hyperbola is

y2

4

−

x2

9

=1
As we know that, equation of vertical hyperbola is given by

y2

a2

−

x2

b2

=1
So, by comparing the given equation of hyperbola with

y2

a2

−

x2

b2

=1 we get,
⇒a2=4 and b2=9
As we know that, eccentricity of a vertical hyperbola is given by e=

√a2+b2

a

So, the eccentricity of given hyperbola is e=

√4+9

2

=

√13

2

Hence, option B is the correct answer