Originally Posted by

**kaemper** Quick question:

A quest states:

In exercises 1-11, calculate div F and curl F for the given vector fields.

11. F = θ̂ (with a "hat" on top) = -sinθi + cosθj.

If I rewrite F in terms of cartesian coordinates I get:

-(y/(√(x^{2 }+ y^{2})) + (x/√(x^{2 }+ y^{2}))

Then by differentiation followed up by addition as the devergence theorem says I get anything but 0, which is the correct result for this task. How come? Have I not converted the polar coordinates into cartesian coordinates correctly? If I can solve this problem, finding the curl of F shouldn't be that hard.