Gradient of a scalar field in a given direction

mudkip9001
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I have to find the gradient of a scalar field, h, at a certain point in a direction given by a vector.

I know, \vec{\nabla}h will give me the direction of maximum slope, and its magnitude is the magnitude of the slope, but i don't know where to start in finding the slope in any other direction. I've looked through my notes and all over the internet, with no luck.
 
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Take the scalar product of \vec{\nabla}h with a unit vector in the given direction.
 
VeeEight said:
Take the scalar product of \vec{\nabla}h with a unit vector in the given direction.

thank you very much! I can't believe i couldn't find that anywhere. I'm happy to tke your word for it, but any chance you have a proof or reference of that for future referance?
 
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