JEE Main 202330 JanuaryMorning Shift
- Exam
- JEE Main
- Year
- 2023
- Date
- 30 January
- Shift
- Morning Shift
- Subject
- Mathematics
- Chapter
- Straight Lines
JEE Main 2023 · 30 January · Morning Shift · Mathematics · Straight Lines
A straight line cuts off the intercepts OA=a and OB=b on the...
A straight line cuts off the intercepts and on the positive directions of -axis and axis respectively. If the perpendicular from origin to this line makes an angle of with positive direction of -axis and the area of is , then is equal to:
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
Plotting the diagram of the given data we get,
Equation of straight line
Here given , so equation of line in intercept form will be
And given perpendicular line of length is making angle with the axis,
So, the equation of line in normal form will be
So, on comparing with the equation \left(1\right)a = 2p \text{ and } b = \dfrac{2p}{\sqrt{3}}OAB\dfrac{1}{2} \times a \times b = \dfrac{98\sqrt{3}}{3}⇒ \dfrac{1}{2} \times 2p \times \dfrac{2p}{\sqrt{3}} = \dfrac{98\sqrt{3}}{3}⇒ {p}^{2} = 49{a}^{2} - {b}^{2} = 4{p}^{2} - \dfrac{4{p}^{2}}{3} = \dfrac{8}{3}{p}^{2}⇒ {a}^{2} - {b}^{2} = \dfrac{8}{3}\left(49\right) = \dfrac{392}{3}