Target Exam

CUET

Subject

Maths. Section B1

Chapter

Continuity and Differentiability

Question:

Differentiate the function $\cos^{-1}(e^x)$ with respect to $x$.

Options:

$\frac{e^x}{\sqrt{1-e^{2x}}}$

$\frac{-e^x}{\sqrt{1-e^x}}$

$\frac{-e^x}{\sqrt{1-e^{2x}}}$

$\frac{-1}{\sqrt{1-e^{2x}}}$

Correct Answer:

$\frac{-e^x}{\sqrt{1-e^{2x}}}$

Explanation:

The correct answer is Option (3) → $\frac{-e^x}{\sqrt{1-e^{2x}}}$ ##

Let $y = \cos^{-1}(e^x)$.

Using chain rule, we have

$\frac{dy}{dx} = \frac{-1}{\sqrt{1-(e^x)^2}} \cdot \frac{d}{dx}(e^x) = \frac{-e^x}{\sqrt{1-e^{2x}}}$