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If the distance between the foci and the distance between the two directricies of the hyperbola `(x^2)/(a^2)-(y^2)/(b^2)=1` are in the ratio 3:2, then `b : a` is (a)`1:sqrt(2)` (b) `sqrt(3):sqrt(2)` (c)`1:2` (d) `2:1`

A

`1:sqrt2`

B

`sqrt3:sqrt2`

C

`1:2`

D

`2:1`

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To solve the problem, we need to find the ratio \( b : a \) given that the distance between the foci and the distance between the two directrices of the hyperbola \( \frac{x^2}{a^2} - \frac{y^2}{b^2} = 1 \) are in the ratio \( 3:2 \). ### Step-by-Step Solution: 1. **Identify the distances**: - The distance between the foci of the hyperbola is given by \( 2ae \), where \( e \) is the eccentricity. - The distance between the directrices is given by \( \frac{2a}{e} \). 2. **Set up the ratio**: - According to the problem, the ratio of the distance between the foci to the distance between the directrices is \( 3:2 \). - Therefore, we can write: \[ \frac{2ae}{\frac{2a}{e}} = \frac{3}{2} \] 3. **Simplify the ratio**: - Simplifying the left-hand side: \[ \frac{2ae \cdot e}{2a} = e^2 \] - Thus, we have: \[ e^2 = \frac{3}{2} \] 4. **Relate eccentricity to \( a \) and \( b \)**: - The eccentricity \( e \) for a hyperbola is defined as: \[ e^2 = 1 + \frac{b^2}{a^2} \] - Substituting \( e^2 = \frac{3}{2} \) into this equation gives: \[ \frac{3}{2} = 1 + \frac{b^2}{a^2} \] 5. **Solve for \( \frac{b^2}{a^2} \)**: - Rearranging the equation: \[ \frac{b^2}{a^2} = \frac{3}{2} - 1 = \frac{1}{2} \] 6. **Find the ratio \( b : a \)**: - Taking the square root of both sides: \[ \frac{b}{a} = \frac{1}{\sqrt{2}} \] - Therefore, the ratio \( b : a \) is: \[ b : a = 1 : \sqrt{2} \] ### Final Answer: The ratio \( b : a \) is \( 1 : \sqrt{2} \), which corresponds to option (a).

To solve the problem, we need to find the ratio \( b : a \) given that the distance between the foci and the distance between the two directrices of the hyperbola \( \frac{x^2}{a^2} - \frac{y^2}{b^2} = 1 \) are in the ratio \( 3:2 \). ### Step-by-Step Solution: 1. **Identify the distances**: - The distance between the foci of the hyperbola is given by \( 2ae \), where \( e \) is the eccentricity. - The distance between the directrices is given by \( \frac{2a}{e} \). ...
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