It's seems like such a basic question but I can't for the life of me remember how to do it.(adsbygoogle = window.adsbygoogle || []).push({});

Given the points A(0,0,1), B(2,3,2), C(1,0,0) and D(2,2,1), verify that the line through A and B and the line through C and D intersect and find the point of intersection P. Find the equation of the line through P which is perpendicular to both these lines.

I've worked out the point P to be (4,6,3) and I know that for a line to be perpendicular, the dot products of two vectors have to be 0.

I know that the equation between A and B isr=k+ P(2i+3j+k) and between C and Dr=i+ Q(i+2j+k).

Am I right in saying that the vector of AB is 2i+3j+kand the vector of CD isi+2j+k?

The answer I worked it out to be isr= 4i+6j+3k+ S(-i+j-k)

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# Homework Help: Vectors question

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