Q214 / 270 · NDA 2017 (Phase 2) · Mathematics
Consider the following :
1. $\mathrm{x}+\mathrm{x}^2$ is continuous at $\mathrm{x}=0$
2. $\mathrm{x}+\cos \frac{1}{\mathrm{x}}$ is discontinuous at $\mathrm{x}=0$
3. $x^2+\cos \frac{1}{x}$ is continuous at $x=0$
Which of the above are correct?
- Correct answerA$1$ and $2$ only
- B$2$ and $3$ only
- C$1$ and $3$ only
- D$1,2$ and $3$
Solution
$\mathrm{x}+\mathrm{x}^2$ is continuous at $\mathrm{x}=0$
$\mathrm{x}+\cos \frac{1}{\mathrm{x}}$ is discontinuous at $\mathrm{x}=0$
$x^2+\cos \frac{1}{x}$ is not continuous at $x=0$.
Hence, the correct answer is option: 'A'.