
myCBSEguide App
CBSE, NCERT, JEE Main, NEET-UG, NDA, Exam Papers, Question Bank, NCERT Solutions, Exemplars, Revision Notes, Free Videos, MCQ Tests & more.
Install Now
Exercise 11.2
In each of the following Exercises 1 to 6, find the coordinates of the focus, axis of the parabola, the equation of the directrix and the length of the latus rectum.
1.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are (3, 0).
Axis of parabola is
Equation of the directrix is
Length of latus rectum =
2.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are
Axis of parabola is
Equation of the directrix is
Length of latus rectum = = 6
3.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are (–2, 0).
Axis of parabola is
Equation of the directrix is
Length of latus rectum =
4.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are
Axis of parabola is
Equation of the directrix is
Length of latus rectum =
5.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are
Axis of parabola is
Equation of the directrix is
Length of latus rectum = = 10
6.
Ans. Given: Equation of parabola
Comparing with we have
Coordinates of focus are
Axis of parabola is
Equation of the directrix is
Length of latus rectum = = 9
In each of the following Exercises 7 to 12, find the equation of the parabola that satisfies the given conditions:
7. Focus (6, 0); directrix
Ans. Given: Directrix : and
Axis of parabola is axis.
The required equation of parabola
8. Focus directrix
Ans. Given: Directrix: and
Axis of parabola is axis.
The required equation of parabola
9. Vertex (0, 0); Focus (3, 0)
Ans. Given: vertex is at (0, 0), and
Axis of parabola is axis.
The required equation of parabola
10. Vertex (0, 0); Focus
Ans. Given: vertex is at (0, 0), and
Axis of parabola is axis.
The required equation of parabola
11. Vertex (0, 0) passing through (2, 3) and axis is along axis.
Ans. Given: vertex (0, 0) and axis is along axis.
Parabola is of the form
Since the parabola passes through the point (2, 3).
The required equation of parabola
12. Vertex (0, 0) passing through (5, 2) and symmetric with respect to axis.
Ans. Given: vertex (0, 0) and axis is along axis.
Parabola is of the form
Since the parabola passes through the point (5, 2).
The required equation of parabola