Target Exam

CUET

Subject

Maths. Section B1

Chapter

Continuity and Differentiability

Question:

Differentiate $a^x$ w.r.t. $x$, where $a$ is a positive constant.

Options:

$x a^{x-1}$

$\frac{a^x}{\ln a}$

$a^x \ln a$

$a^x$

Correct Answer:

$a^x \ln a$

Explanation:

The correct answer is Option (3) → $a^x \ln a$ ##

Let $y = a^x$. Then

$\log y = x \log a$

Differentiating both sides w.r.t. $x$, we have

$\frac{1}{y} \frac{dy}{dx} = \log a$

or $\frac{dy}{dx} = y \log a$

Thus $\frac{d}{dx}(a^x) = a^x \log a$