Target Exam

CUET

Subject

Section B1

Chapter

Continuity and Differentiability

Question:

Match List-I with List-II

List-I Function

List-II Property

(A) $f(x) =\left\{\begin{matrix}\frac{x}{|x|}&:x≠0\\0&:x=0\end{matrix}\right.$

(I) continuous but not differentiable at $x= 0$

(B) $f(x) = |x|$

(II) continuous but not differentiable at $x=1$

(C) $f(x) = |x^2 – 1|$

(III) discontinuous at $x = 0$

(D) $f(x) = |x – 1|$

(IV) continuous but not differentiable at $x =1, -1$

Choose the correct answer from the options given below:

Options:

(A)-(III), (B)-(I), (C)-(IV), (D)-(II)

(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

(A)-(III), (B)-(I), (C)-(II), (D)-(IV)

(A)-(IV), (B)-(III), (C)-(I), (D)-(II)

Correct Answer:

(A)-(III), (B)-(I), (C)-(IV), (D)-(II)

Explanation:

The correct answer is Option (1) → (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

List-I Function

List-II Property

(A) $f(x) =\left\{\begin{matrix}\frac{x}{|x|}&:x≠0\\0&:x=0\end{matrix}\right.$

(III) discontinuous at $x = 0$

(B) $f(x) = |x|$

(I) continuous but not differentiable at $x= 0$

(C) $f(x) = |x^2 – 1|$

(IV) continuous but not differentiable at $x =1, -1$

(D) $f(x) = |x – 1|$

(II) continuous but not differentiable at $x=1$

(A) $f(x)=\begin{cases}\frac{x}{|x|},&x\ne 0\\0,&x=0\end{cases}$

Left and right limits at $0$ are $-1$ and $1$, so $f$ is discontinuous at $0$.

So (A) → (III).

(B) $f(x)=|x|$ is continuous everywhere but not differentiable at $x=0$.

So (B) → (I).

(C) $f(x)=|x^{2}-1|$ is continuous everywhere but not differentiable where $x^{2}-1=0$, i.e., $x=1,-1$.

So (C) → (IV).

(D) $f(x)=|x-1|$ is continuous everywhere but not differentiable at $x=1$.

So (D) → (II).

Final answer: (A)–(III), (B)–(I), (C)–(IV), (D)–(II)