Maharashtra Board Class 11 Maths Part 1 Chapter 7 Conic Sections Ex 7.3 Solution

Question 1.
Find the length of the transverse axis, length of conjugate axis, the eccentricity, the co-ordinates of foci, equations of directrices, and the length of the latus rectum of the hyperbolae.
word image 18221 1

word image 18221 2

word image 18221 3
⇒ b = 4 and a = 5
Length of transverse axis = 2b = 2(4) = 8
Length of conjugate axis = 2a = 2(5) = 10
Co-ordinates of vertices are B(0, b) and B’ (0, -b)
i.e., B(0, 4) and B'(0, -4)
We know that
word image 18221 4

word image 18221 5
word image 18221 6
word image 18221 7
word image 18221 8
word image 18221 9
word image 18221 10

word image 18221 11
Length of transverse axis = 2b = 2(5) = 10
Length of conjugate axis = 2a = 2(3) = 6
Co-ordinates of vertices are B(0, b) and B’ (0, -b),
i.e., B(0, 5) and B’ (0, -5)
We know that
word image 18221 12

word image 18221 13
⇒ b = 5 and a = 12
Length of transverse axis = 2b = 2(5) = 10
Length of conjugate axis = 2a = 2(12) = 24
Co-ordinates of vertices are B(0, b) and B’ (0, -b),
i.e., B(0, 5) and B’ (0, -5)
We know that
word image 18221 14

word image 18221 15
⇒ a = 10 and b = 5
Length of transverse axis = 2a = 2(10) = 20
Length of conjugate axis = 2b = 2(5) = 10
We know that
word image 18221 16

word image 18221 17

Question 2.
Find the equation of the hyperbola with centre at the origin, length of the conjugate axis as 10, and one of the foci as (-7, 0).
Solution:

word image 18221 18

Question 3.
word image 18221 19

Question 4.

Solution:

Let e be the eccentricity of a hyperbola
word image 18221 21
word image 18221 22

Question 5.
word image 18221 23
word image 18221 24

word image 18221 25
word image 18221 26
Maharashtra Board 11th Maths Solutions Chapter 7 Conic Sections Ex 7.3 Q5 (iii)
word image 18221 28
word image 18221 29
word image 18221 30

(v) Let the required equation of hyperbola be
word image 18221 31
The hyperbola passes through the points (6, 9) and (3, 0).
word image 18221 32

word image 18221 33
word image 18221 34
word image 18221 35
word image 18221 36

Question 6.

Solution:

word image 18221 38
word image 18221 39
word image 18221 40
word image 18221 41
word image 18221 42
word image 18221 43
word image 18221 44
word image 18221 45

Question 7.
word image 18221 46
word image 18221 47

Question 8.
word image 18221 48

Alternate method:
word image 18221 49

Question 9.

Question 10.