The focus of the curve : coincides with the right focus of the curve : , and the line connecting the intersection points of the curves and passes through point . What is the eccentricity of the curve ?
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Solution
The focus of the curve : is . Therefore, the value of for the hyperbola is .
Since the line connecting the intersection points of the curves and passes through point , by symmetry, this line is perpendicular to the -axis. Let , and substitute it into the equation of the hyperbola:
Solving for , we get , and thus the length of the chord .
Now, let , and substitute it into the equation of the parabola:
This gives us , and thus the length of the chord .
Equating the two expressions for , we get:
This simplifies to . Solving for the eccentricity , we have:
Solving this quadratic equation for , we obtain .
Answer:
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