A 3-dimensional graph has infinite number of derivatives (in different directions) at a single point. I've learned how to find the partial derivative with respect to x and y, simply taking y and x to be constant respectively. But what do I do if I want to take the partial derivative with respect to a line that is not in the direction of an axis, but rather a diagonal line, like a line cutting through the x-axis at 45 degrees? In this case you can't simply take one of the axis to be a constant, right?(adsbygoogle = window.adsbygoogle || []).push({});

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# Partial Derivatives with Respect To Lines That Are Not In The Direction of Axis

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