Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Applications of Derivatives

Question:

The slope of the normal to the curve $y=x^3+3 x-2$ at its point of intersection with y-axis is:

Options:

3

-3

$\frac{1}{3}$

$-\frac{1}{3}$

Correct Answer:

$-\frac{1}{3}$

Explanation:

The correct answer is Option (4) → $-\frac{1}{3}$

$\frac{dy}{dx}=3x^2+3$

when it intersects y axis ⇒ x = 0

⇒ tangent = $\frac{dy}{dx}=3$ so normal

$=-\frac{dx}{dy}=-\frac{1}{3}$