Q46 / 120 · VITEEE 2017 · Mathematics
Equation $\frac{1}{r}=\frac{1}{8}+\frac{3}{8} \cos \theta$ represents
- AA rectangular hyperbola
- Correct answerBA hyperbola
- CAn ellipse
- DA parabola
Solution
Given, equation is
$$
\frac{1}{r}=\frac{1}{8}+\frac{3}{8} \cos \theta \text { or } \frac{8}{\mathrm{r}}=1+3 \cos \theta
$$
which is the form of $\frac{l}{r}=1+e \cos \theta$
$$
\because \quad e=3>0
$$
$\therefore \quad$ Given equation is a hyperbola.
Hence, the correct answer is option: 'B'.