At any point of a curve $\sqrt{\frac{\text {subnormal}}{\text {subtangent}}}$ is equal to
Answer & explanation
Correct answer: option 3
We have,
Sub normal = $y \frac{d y}{d x}$, Sub-tangent = $\frac{y}{\frac{d y}{d x}}$
$\Rightarrow \sqrt{\frac{\text {Sub normal}}{\text {Sub tangent}}}=\sqrt{\frac{y \frac{d y}{d x}}{\frac{y}{\frac{d y}{d x}}}} = \frac{d y}{d x}$ = Slope of the tangent