Questions number 19 and 20 are Assertion – Reason based questions of 1 mark each. Two statements are given – one labelled Assertion (A) and other…

Questions number $\displaystyle 19$ and $\displaystyle 20$ are Assertion – Reason based questions of $\displaystyle 1$ mark each. Two statements are given – one labelled Assertion (A) and other labelled Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below : Assertion (A): The differential equation representing the family of curves $\displaystyle \mathrm{y}=\mathrm{m} x$, m being an arbitrary constant, is $$x \frac{\mathrm{dy}}{\mathrm{d} x}-\mathrm{y}=0 . $$ Reason (R): For a family of curves, the differential equation is obtained by differentiating the equation of family of curves with respect to $\displaystyle x$ and then eliminating the arbitrary constant, if any.