Hello,

I'm having trouble answering this question.

Q: Relative to the origin O, the point A has position vector given by OA = i + 2j + 4k. The line lhas

equation r = 9i − j + 8k + 3i − j + 2k.Find the position vector of the foot of the perpendicular from A to l. Hence find the position

vector of the reflection of A in l.

I found the position vector of the foot of the perpendicular as 3/2i + 3/2j + 3k.

But I don't understand how to answer the second part.

I appreciate your help.

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