Q73 / 155 · WBJEE 2020 · Mathematics
The equation $r \cos \left(\theta-\frac{\pi}{3}\right)=2$ represents
- Aa circle
- Ba parabola
- Can ellipse
- Correct answerDa straight line
Solution
Hint:
$r \cos \left(\theta-\frac{\pi}{3}\right)=2 \quad \Rightarrow r \cos \theta \times \frac{1}{2}+r \sin \theta \times \frac{\sqrt{3}}{2}=2 \Rightarrow x+\sqrt{3} y=4(x=r \cos \theta, y=r \sin \theta)$
$\therefore$ a straight line
Hence, the correct answer is option: 'D'.