Hello. I need some help with the following problem:(adsbygoogle = window.adsbygoogle || []).push({});

Find the component of u if u is perpendicular to the plane x- 3y + 4z =0 and the magnitude of u is 3.

My work:

Some vector v is on the plane

v = 1i – 3j + 4k

so then the dot product of u and v = 0

Now I’m stuck and don’t know where to go from here.

The answer in the back of the book is: [3/sqrt 26]i - [9/sqrt 26]j + [12/sqrt 26]k

Any help would be greatly appreciated.

Thanks

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# Homework Help: Vectors and planes

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