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Question
The parabola y2 = kx passes through the point (4, -2). Find its latus rectum and focus.
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Solution
y2 = kx passes through (4, -2)
(-2)2 = k(4)
⇒ 4 = 4k
⇒ k = 1
y2 = x = 4`(1/4)`x
a = `1/4`
Equation of LR is x = a or x – a = 0
i.e., x = `1/4`
⇒ 4x = 1
⇒ 4x – 1 = 0
Focus (a, 0) = `(1/4,0)`
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