The descending order of magnitude of the eccentricities of the following hyperbolas is:
A. A hyperbola whose distance between foci is three times the distance between its directrices.
B. Hyperbola in which the transverse axis is twice the conjugate axis.
C. Hyperbola with asymptotes \( x + y + 1 = 0, x - y + 3 = 0 \).
Show Hint
The eccentricity of a hyperbola is always greater than 1 and can be determined using the transverse and conjugate axis relations.
Step 1: Finding the eccentricities
For a hyperbola, the eccentricity is given by:
\[
e = \frac{\text{distance between foci}}{\text{length of transverse axis}}.
\]
Solving for each case:
- Hyperbola A: Given condition leads to \( e = \frac{3}{2} \).
- Hyperbola B: \( e = \sqrt{5}/2 \).
- Hyperbola C: Given asymptotes suggest \( e = \sqrt{2} \).
Ordering the values, we get:
\[
A > C > B.
\]