RegionMeasure

RegionMeasure[reg] gives the measure of the region reg.

RegionMeasure[reg,d] gives the d-dimensional measure of the region reg.

RegionMeasure[{x1,…,xn},{{t1,a1,b1},…,{tk,ak,bk}}] gives the k-measure of the parametric formula whose Cartesian coordinates xi are functions of tj.

RegionMeasure[{x1,…,xn},{{t1,a1,b1},…,{tk,ak,bk}},chart] interprets the xi as coordinates in the specified coordinate chart.

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