NTA Abhyas JEE Main2020MathematicsDifferential EquationsPractice
A curve in the first quadrant is such that the slope of O P is twice the slope of the tangent drawn at P to the curve, where O is the origin and P is any general point on the curve. If the curve passes through 4 , 2 , then its equation is
Options
- Ay = x 2 - 14
- By 2 = x
- Cy = x 3 - 62
- Dy = sin x - 4 + 2
Correct answer
B. y 2 = x
Step-by-step solution
Slope of O P = 2 d y d x P ⇒ y x = 2 d y d x ⇒ 2 ∫ d y y = ∫ d x x ⇒ 2 ln y = ln x + ln c ⇒ y 2 = c x As it passes through 4 , 2 ⇒ c = 1 ∴ the equation of the curve is y 2 = x