Q48 / 90 · JEE Main 2019 (12 Apr Shift 2) · Mathematics

If the area (in sq. units) bounded by the parabola y2=4λx and the line y=λx, λ>0, is 19, then λ is equal to

  • A
    43
  • B
    26
  • C
    48
  • Correct answer
    D
    24

Solution

The given equations are y2=4λx and y=λx

Using above equations, we can write

λx2=4λx⇒λ2x2-4λx=0

⇒λxλx-4=0

⇒x=0 & x=4λ

Figure

Area =19=∫04λ4λx-λxdx

⇒4λx3232-λx2204λ=19

⇒λ=24

Hence, the required value is 24.

Hence, the correct answer is option: 'D'.

Relevant Questions