Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
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 OA=a\mathrm{OA}=\mathrm{a} and OB=b\mathrm{OB}=\mathrm{b} on the positive directions of x\mathrm{x}-axis and y−\mathrm{y}- axis respectively. If the perpendicular from origin O\mathrm{O} to this line makes an angle of π6\frac{\pi}{6} with positive direction of yy-axis and the area of △OAB\triangle \mathrm{OAB} is 9833\frac{98}{3} \sqrt{3}, then a2−b2\mathrm{a}^2-\mathrm{b}^2 is equal to:A straight line cuts off the intercepts OA=a and OB=b on the positive directions of x -axis and y- axis respectively.

Options

  1. A3923\dfrac{392}{3}
  2. B196196
  3. C1963\dfrac{196}{3}
  4. D9898

Correct answer

A. 3923\dfrac{392}{3}

Step-by-step solution

Plotting the diagram of the given data we get,

A straight line cuts off the intercepts OA=a and OB=b on the positive directions of x -axis and y- axis respectively.

Equation of straight line

Here given OA=a and OB=bOA = a \text{ and } OB = b, so equation of line ABAB in intercept form will be xa+yb=1......(1)\dfrac{x}{a} + \dfrac{y}{b} = 1 . . . . . . \left(1\right)

And given perpendicular line of length pp is making π3\dfrac{\pi}{3} angle with the x−x -axis,

So, the equation of line in normal form will be

xcos(π3)+ysin(π3)=pxcos\left(\dfrac{\pi}{3}\right) + ysin\left(\dfrac{\pi}{3}\right) = p

⇒x2p+y32p=1⇒ \dfrac{x}{2p} + \dfrac{y\sqrt{3}}{2p} = 1

So, on comparing with the equation \left(1\right)weget,</p><p>we get,</p><p>a = 2p \text{ and } b = \dfrac{2p}{\sqrt{3}}</p><p>Nowareaofthetriangle</p><p>Now area of the triangleOABis</p><p>is </p><p>\dfrac{1}{2} \times a \times b = \dfrac{98\sqrt{3}}{3}</p><p></p><p>⇒ \dfrac{1}{2} \times 2p \times \dfrac{2p}{\sqrt{3}} = \dfrac{98\sqrt{3}}{3}</p><p></p><p>⇒ {p}^{2} = 49</p><p>Therefore,</p><p></p><p>Therefore,</p><p>{a}^{2} - {b}^{2} = 4{p}^{2} - \dfrac{4{p}^{2}}{3} = \dfrac{8}{3}{p}^{2}</p><p></p><p>⇒ {a}^{2} - {b}^{2} = \dfrac{8}{3}\left(49\right) = \dfrac{392}{3}

Practice Straight Lines on Quantrex Academy →

More from Straight Lines

If a straight line drawn through the point of intersection of the lines 4x+3y-1=0 and… JEE Main 2026From the point (-1, -1) , two rays are sent making angles of 45° with the line x + y = 0… JEE Main 2026In an equilateral triangle PQR , let the vertex P be at (3, 5) and the side QR be along… JEE Main 2026Let P(3 α, 2 α) , α ≠ 0 , be a point on the ellipse (x^2)/(9)+(y^2)/(4)=1 , Q be a point… JEE Main 2026Let A,B be points on the two half-lines x- 3 |y|=α , α>0 at a distance of α from their… JEE Main 2026Let the line L_1 : x + 3 = 0 intersect the lines L_2 : x - y = 0 and L_3 : 3x + y = 0 at… JEE Main 2026Let the vertex A of a triangle ABC be (1, 2) , and the mid-point of the side AB be (5… JEE Main 2026Let the mid points of the sides of a triangle ABC be ((5)/(2), 7) , ((5)/(2), 3) and (4… JEE Main 2026Let ABC be an equilateral triangle with orthocenter at the origin and the side BC on the… JEE Main 2026Let the angles made with the positive x -axis by two straight lines drawn from the point… JEE Main 2026Let A(1,0), B(2,-1) and C((7)/(3), (4)/(3)) be three points. If the equation of the… JEE Main 2026Let A(1,2) and C(-3,-6) be two diagonally opposite vertices of a rhombus, whose sides AD… JEE Main 2026A rectangle is formed by the lines x=0, y=0, x=3 and y=4 . Let the line L be… JEE Main 2026Among the statements (S 1) : If A(5,-1) and B(-2,3) are two vertices of a triangle, whose… JEE Main 2026Let a point A lie between the parallel lines L_ 1 and L_ 2 such that its distances from… JEE Main 2026A line passing through the point P(a, θ) makes an acute angle α with the positive x… JEE Main 2025 Full Straight Lines list Straight Lines JEE Maths PYQsJEE Mathematics PYQs All JEE Main PYQs