Taylor series review

Then if the gradient of f at a point P of S is not the zero vector, it is a normal vector of S at P. [Example] Find the normal of the curve. f(x, y) = ln(x2 + y2) = constant. Since (f the surface of f = constant, (f = i + j = i + j [Example] Find the unit normal to the surface of . f(x, y, z) = x y3 z2 = 4 at (-1, -1, 2). ................
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