ExamBro
ExamBro
TS EAMCET · Maths · Application of Derivatives

If at any point \(\left(x_1, y_1\right)\) on the curve \(y=f(x)\) the lengths of the subtangent and subnormal are equal, then the length of the tangent drawn to that curve at that point is

  1. A \(2\left|y_1\right|\)
  2. B \(\sqrt{2}\left|y_1\right|\)
  3. C \(\sqrt{5}\left|y_1\right|\)
  4. D \(\sqrt{2}\left|\frac{y_1}{x_1}\right|\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(\sqrt{2}\left|y_1\right|\)

Step-by-step Solution

Detailed explanation

We have, Length of subtangent \(=\) Length of subnormal \(\therefore \quad y_1 \frac{d x}{d y}=y_1 \frac{d y}{d x}\) \(\Rightarrow \quad \frac{d y}{d x}= \pm 1\) Length of tangent \(=\left|y_1 \sqrt{1+\left(\frac{d x}{d y}\right)^2}\right|\) Length of tangent…
From TS EAMCET
Explore more questions on app