Perimeter

Perimeter[reg] gives the perimeter of the two-dimensional region reg.

Perimeter[{x1,x2},{s,smin,smax},{t,tmin,tmax}] gives the perimeter of the parametrized region whose Cartesian coordinates xi are functions of s and t.

Perimeter[{x1,x2},{s,smin,smax},{t,tmin,tmax},chart] interprets the xi as coordinates in the specified coordinate chart.

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