MENU
Question -

Find the eccentricity, coordinatesof foci, length of the latus – rectum of the following ellipse:
(i) 4x2 + 9y2 = 1

(ii) 5x2 + 4y2 =1

(iii) 4x2 + 3y2 =1

(iv) 25x2 + 16y2 =1600

(v) 9x2 + 25y2 =225



Answer -

(i) 4x2 + 9y2 = 1

Given:

The equation of ellipse => 4x2 + 9y2 =1

This equation can be expressed as

By using the formula,

Eccentricity:

Here, a2 = ¼, b2 = 1/9

Length of latus rectum = 2b2/a

= [2 (1/9)] / (1/2)

= 4/9

Coordinates of foci (±ae, 0)

(ii) 5x2 + 4y2 = 1

Given:

The equation of ellipse => 5x2 + 4y2 =1

This equation can be expressed as

By using the formula,

Eccentricity:

Here, a2 = 1/5 and b2 = ¼

Length of latus rectum = 2b2/a

= [2(1/5)] / (1/2)

= 4/5

Coordinates of foci (±ae, 0)

(iii) 4x2 + 3y2 = 1

Given:

The equation of ellipse => 4x2 + 3y2 =1

This equation can be expressed as

By using the formula,

Eccentricity:

Here, a2 = 1/4 and b2 = 1/3

Length of latus rectum = 2b2/a

= [2(1/4)] / (1/√3)

= √3/2

Coordinates of foci (±ae, 0)

(iv) 25x2 + 16y2 = 1600

Given:

The equation of ellipse => 25x2 + 16y2 =1600

This equation can be expressed as

By using the formula,

Eccentricity:

Here, a2 = 64 and b2 = 100

Length of latus rectum = 2b2/a

= [2(64)] / (100)

= 32/25

Coordinates of foci (±ae, 0)


(v) 9x2 + 25y2 = 225

Given:

The equation of ellipse => 9x2 + 25y2 =225

This equation can be expressed as

By using the formula,

Eccentricity:

Here, a2 = 25 and b2 = 9

Length of latus rectum = 2b2/a

= [2(9)] / (5)

= 18/5

Coordinates of foci (±ae, 0)

Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
×