The area of the region bounded by the parabola y2 = 4kx, where k > 0 and its latus rectum is 24 square units. What is the value of k ?

This question was previously asked in
NDA 01/2022: Maths Previous Year paper (Held On 10 April 2022)
View all NDA Papers >
  1. 1
  2. 2
  3. 3
  4. 4

Answer (Detailed Solution Below)

Option 3 : 3
Free
NDA 01/2025: English Subject Test
30 Qs. 120 Marks 30 Mins

Detailed Solution

Download Solution PDF

Calculation:

The equation of parabola is y= 4kx      ------(1)

Let O be the vertex, S be the focus, and LL' be the latus rectum of the parabola.

The equation of latus rectum is x = k.

Also, here the parabola is symmetric about x−axis.

Required area, A = 2(area of OSL)

⇒ Required area, A = 2 

 A = 2 

 A = 2.2√k 

 A = 4√k 

 A = 

 A = 

Since the area of the given parabola is 24.

 24 = 

⇒ k = ± 3

As the value of  k > 0, k = 3.

∴ The value of k = 3.

Latest NDA Updates

Last updated on Jun 18, 2025

->UPSC has extended the UPSC NDA 2 Registration Date till 20th June 2025.

-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.

->The NDA exam date 2025 has been announced. The written examination will be held on 14th September 2025.

-> The selection process for the NDA exam includes a Written Exam and SSB Interview.

-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100. 

-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential. 

Hot Links: dhani teen patti teen patti casino teen patti real