A) \[\frac{1}{a}\]
B) a
C) \[2a\]
D) \[\frac{1}{2a}\]
Correct Answer: A
Solution :
Equation of parabola \[{{y}^{2}}=4ax\] Total length of focal chord = 4a and half length of focal chord = 2a Now, sum of the reciprocals of focal distances \[=\frac{1}{2a}+\frac{1}{2a}=\frac{2}{2a}=\frac{1}{a}\]You need to login to perform this action.
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