Home
Class 12
MATHS
If the area of the triangle whose one ve...

If the area of the triangle whose one vertex is at the vertex of the parabola, `y^(2) + 4 (x - a^(2)) = 0` and the other two vertices are the points of intersection of the parabola and Y-axis, is 250 sq units, then a value of 'a' is

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of 'a' given the area of the triangle formed by the vertex of the parabola and the points of intersection of the parabola with the Y-axis. ### Step 1: Identify the parabola and its vertex The given equation of the parabola is: \[ y^2 + 4(x - a^2) = 0 \] Rearranging it gives: \[ y^2 = -4(x - a^2) \] This represents a parabola that opens to the left. The vertex of the parabola occurs at the point where \( x = a^2 \) and \( y = 0 \). Therefore, the vertex is: \[ V(a) = (a^2, 0) \] ### Step 2: Find the points of intersection with the Y-axis To find the points of intersection with the Y-axis, we set \( x = 0 \) in the equation of the parabola: \[ y^2 = -4(0 - a^2) = 4a^2 \] Taking the square root gives: \[ y = 2a \quad \text{and} \quad y = -2a \] Thus, the points of intersection with the Y-axis are: \[ P_1(0, 2a) \quad \text{and} \quad P_2(0, -2a) \] ### Step 3: Calculate the area of the triangle The area \( A \) of a triangle formed by the vertices \( V(a) \), \( P_1 \), and \( P_2 \) can be calculated using the formula: \[ A = \frac{1}{2} \times \text{base} \times \text{height} \] Here, the base is the distance between \( P_1 \) and \( P_2 \) along the Y-axis, which is: \[ \text{base} = |2a - (-2a)| = |2a + 2a| = 4a \] The height of the triangle is the horizontal distance from the vertex \( V(a) \) to the Y-axis, which is: \[ \text{height} = a^2 \] Thus, the area of the triangle is: \[ A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 4a \times a^2 = 2a^3 \] ### Step 4: Set the area equal to 250 and solve for 'a' According to the problem, the area of the triangle is given as 250 square units: \[ 2a^3 = 250 \] Dividing both sides by 2: \[ a^3 = 125 \] Taking the cube root of both sides: \[ a = 5 \] ### Conclusion The value of 'a' is: \[ \boxed{5} \]

To solve the problem, we need to find the value of 'a' given the area of the triangle formed by the vertex of the parabola and the points of intersection of the parabola with the Y-axis. ### Step 1: Identify the parabola and its vertex The given equation of the parabola is: \[ y^2 + 4(x - a^2) = 0 \] Rearranging it gives: ...
Promotional Banner

Topper's Solved these Questions

  • PARABOLA

    IIT JEE PREVIOUS YEAR|Exercise TOPIC 1 EQUATION OF PARABOLA AND FOCAL CHORD (ASSERTION AND REASON )|1 Videos
  • PARABOLA

    IIT JEE PREVIOUS YEAR|Exercise TOPIC 1 EQUATION OF PARABOLA AND FOCAL CHORD (INTERGER )|2 Videos
  • MISCELLANEOUS

    IIT JEE PREVIOUS YEAR|Exercise MISCELLANEOUS|87 Videos
  • PERMUTATIONS AND COMBINATIONS

    IIT JEE PREVIOUS YEAR|Exercise Dearrangement and Number of Divisors (Fill in the Blank )|1 Videos

Similar Questions

Explore conceptually related problems

The vertex of the parabola y ^(2) -4y-x+3=0 is

The vertex of the parabola y^(2)+6x-2y+13=0 is

The coordinates of the vertex of the parabola y^(2)=4(x+y) is

Vertex of the parabola x ^(2) +4x + 2y -7=0 is

Vertex of the parabola y ^(2) + 2y + x=0 lies in the

Find the area of the triangle formed by the lines joining the vertex of the parabola y^(2) = 16x to the ends of the latus rectum.

The vertex of the parabola x^(2)+y^(2)-2xy-4x-4y+4=0 is at

Find the area of the triangle formed by the lines joining the vertex of the parabola x^2 = - 36y to the ends of the latus rectum.

Find the area of the triangle formed by the lines joining the vertex of the parabola x^(2) = 8y to the ends of its latus rectum.