QJEEM24Mae9f9: JEE Main 2024 Mathematics - Class 11 JEEM24Mae9f9 Solution: Let the foci of a hyperbola coincide with the foci of the…
Let the foci of a hyperbola H coincide with the foci of the ellipse E:100(x−1)2+75(y−1)2=1 and the eccentricity of the hyperbola H be the reciprocal of the eccentricity of the ellipse E. If the length of the transverse axis of H is α and the length of its conjugate axis is β, then 3α2+2β2 is equal to
Multiple Choice Options
A225
B237
C242
D205
Step-by-Step Verified Solution
E:100(x−1)2+75(y−1)2=1
Eccentricity of ellipse, eEamp;=1−a2b2amp;=1−10075amp;eE=21
∴eH=2 [ as eccentricity of hyperbola is reciprocal of eccentricity of ellipse]
Transverse axis of hyperbola =α
Conjugate axis of hyperbola =β
Also, foci of ellipse (1±ae,1)
amp;=(1±(10×21),1)amp;=(1±5,1)amp;=(6,1) and (−4,1)
Distance between foci =10
amp;2ae=10amp;⇒a=25
amp; also, e2=1+a2b2amp;4b2bamp;=1+254b2amp;=475amp;=275amp;⇒α=5amp; and β=75amp;3α2+2β2=3(5)2+2(75)=225