According to the statement(attached file) in order to find the directional derivative I must know unit vector along the direction and the point at which to find the directional derivatives. From the angle I can find out the direction (as the cosine of the angle) but not the point. Then how can I solve this question?(adsbygoogle = window.adsbygoogle || []).push({});

Your help is much appreciated.

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# Homework Help: Directional derivatives

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