NCERT Class XI Mathematics - Conic Sections - Solutions

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Question : 51
Total: 71
16x29y2 = 576
Solution:  
Given equation of hyperbola is 16x29y2 = 576
i.e.,
16x2
576
9y2
576
= 1 ⇒
x2
36
y2
64
= 1 which is of the form
x2
a2
y2
b2
= 1.
The foci and vertices of the hyperbola lie on x-axis.
Now, a2 = 36 ⇒ a = 6 and b2 = 64 ⇒ b = 8
Also, c2 = a2+b2 = 36 + 64 = 100 ⇒ c = 10
∴ Coordinates of foci are (± c, 0) i.e, (±10, 0)
∴ Coordinates of vertices are (± a, 0) i.e. (± 6, 0)
Eccentricity (e) =
c
a
=
10
6
=
5
3

Length of latus rectum =
2b2
a
=
2×64
6
=
64
3
.
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