A vector field, such as its expansion or compression (divergence) and its rotation (curl), are intrinsic to the field itself and don't depend on the coordinate system used to describe them. Even though the formulas for divergence and curl look vastly different in Cartesian, cylindrical, and spherical coordinates, applying them to the same vector field will always give the same result.
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$\complement\cdots$Counselor
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The core takeaway is that the fundamental properties of vector fields, such as their divergence (source/sink) and curl (rotation), are independent of the coordinate system used to describe them. Even though the mathematical expressions for divergence and curl are different in Cartesian, cylindrical, and spherical coordinates, applying them to the same vector field (in this case, the position vector $x$ ) consistently yields the same results: $\nabla \cdot x=3$ and $\nabla \times x=0$.
The analysis reinforces the geometric meaning of divergence and curl.
The problem serves as a practical exercise in applying the coordinate-specific formulas for vector operators. Successfully performing the calculation in all three systems and confirming the consistency of the results demonstrates the robustness and elegance of vector calculus as a tool for describing physical phenomena.
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