Home
Class 12
MATHS
If axis of the parabola lie along y-axis...

If axis of the parabola lie along y-axis and if vertex is at a distance of 2 from origin on positive y-axis, focus is at a distance of 2 from origin on negative y-axis then which of the following points doesn't lie on the parabola:

A

`(4sqrt(2), 0)`

B

`(4,1)`

C

`(-4, -2)`

D

`(8, - 2)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to determine the equation of the parabola based on the given information and then check which of the provided points does not lie on the parabola. ### Step 1: Understand the Parabola's Properties Given: - The axis of the parabola lies along the y-axis. - The vertex is at a distance of 2 from the origin on the positive y-axis, which means the vertex is at (0, 2). - The focus is at a distance of 2 from the origin on the negative y-axis, which means the focus is at (0, -2). ### Step 2: Determine the Value of 'a' The distance between the vertex and the focus is denoted by 'a'. Here, the vertex is at (0, 2) and the focus is at (0, -2). Thus: - The distance 'a' = |2 - (-2)| = 4. ### Step 3: Write the Equation of the Parabola The standard form of a parabola that opens downwards with vertex at (h, k) is given by: \[ (x - h)^2 = -4a(y - k) \] Substituting the values: - \(h = 0\), \(k = 2\), and \(a = 4\): \[ x^2 = -16(y - 2) \] This simplifies to: \[ x^2 = -16y + 32 \quad \text{or} \quad x^2 + 16y - 32 = 0 \] ### Step 4: Check Each Point Now we will check each of the provided points to see if they satisfy the equation of the parabola. 1. **Point (4√2, 0)**: \[ (4\sqrt{2})^2 + 16(0) - 32 = 32 - 32 = 0 \quad \text{(lies on the parabola)} \] 2. **Point (4, 1)**: \[ (4)^2 + 16(1) - 32 = 16 + 16 - 32 = 0 \quad \text{(lies on the parabola)} \] 3. **Point (-4, -2)**: \[ (-4)^2 + 16(-2) - 32 = 16 - 32 - 32 = -48 \quad \text{(does not lie on the parabola)} \] ### Conclusion The point that does not lie on the parabola is **(-4, -2)**.

To solve the problem, we need to determine the equation of the parabola based on the given information and then check which of the provided points does not lie on the parabola. ### Step 1: Understand the Parabola's Properties Given: - The axis of the parabola lies along the y-axis. - The vertex is at a distance of 2 from the origin on the positive y-axis, which means the vertex is at (0, 2). - The focus is at a distance of 2 from the origin on the negative y-axis, which means the focus is at (0, -2). ...
Promotional Banner

Topper's Solved these Questions

  • JEE MAIN REVISION TEST - 18

    VMC MODULES ENGLISH|Exercise MATHEMATICS - SECTION 2|5 Videos
  • JEE MAIN REVISION TEST - 13

    VMC MODULES ENGLISH|Exercise MATHEMATICS (SECTION 2)|5 Videos
  • JEE MAIN REVISION TEST - 19

    VMC MODULES ENGLISH|Exercise MATHEMATICS|25 Videos

Similar Questions

Explore conceptually related problems

Axis of a parabola lies along x-axis. If its vertex and focus are at distances 2 and 4, respectively, from the origin on the positive x-axis, then which of the following points does not lie on it ?

There si a parabola having axis as x -axis, vertex is at a distance of 2 unit from origin & focus is at (4,0) . Which of the following point does not lie on the parabola. (a) (6,8) (b) (5,2sqrt(6)) (c) (8,4sqrt(3)) (d) (4,-4)

Find the equation of the parabola whose vertex and focus are on the positive X-axis at a distance of a and a' from the origin respectively.

The point which lies on Y-axis at a distance of 5 units in the negative direction of Y-axis is

The axis of a parabola is along the line y = x and its vertex and focus are in the first quadrant at distances sqrt2,2sqrt2 respectively, from the origin. The equation of the parabola, is

The vertex and focus of a parabola are at a distance of h and k units on positive x-axis from origin. Then equation of parabola is

Find the equation of the circles which touch the axis of x at a distance of 4 from the origin and cut off an intercept of 6 from the axis of y.

Find the equation of the circle which touches the y-axis at a distance of +4 from the origin and cuts off an intercept 6 from the x-axis.

Find the locus of the point such that its distance from the x-axis is half its distance from the y-axis.

Find the equations of the circles passing through two points on y-axis at distance 3 from the origin and having radius 5.