Q. A curve having the condition that the slope of tangent at some point is two times the slope of the straight line joining the same point to the origin of coordinates, is a/an

A) Circle
B) Ellipse
C) Parabola
D) Hyperbola
Explanation

(c)
Given, $\frac{dy}{dx} = 2\ \frac{y}{x}$ $(\therefore y = mx)$
$\Rightarrow$ $\int_{}^{}\frac{dy}{y} = 2\int_{}^{}\frac{dx}{x}$
$\Rightarrow$ $\log y = 2\log x + \log c$
$\Rightarrow$ $y = cx^{2}$
Which represent a parabola of the form
$x^{2} = 4ay$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.