Question

The differential equation of all the lines in the xy-plane is

• A. $\frac{dy}{dx}-x=0$
• B. $\frac{d^{2}y}{d{x}^2}-x\frac{dy}{dx}=0$
• C. $\frac{d^{2}y}{d{x}^2}=0$
• D. $\frac{d^{2}y}{d{x}^2}+x=0$

Answer 1

The correct option is C

$\frac{d^{2}y}{d{x}^2}=0$

The equation of all the lines in xy - plane is given
by y = mx + c
Differentiate it twice w.r.t. x, we get $\frac{d^{2}y}{d{x}^2}=0.$