API Reference > geometry-core > ArraysAndInterfaces > IndexedXYCollection > crossProductIndexIndexIndex crossProductIndexIndexIndex MethodAbstract Return the cross product of vectors from origin point at indexA to target points at indexB and indexC crossProductIndexIndexIndex(origin: number, indexA: number, indexB: number): undefined | number Parameter Type Description origin number index of origin indexA number index of first target within the array indexB number index of second target within the array Returns - undefined | number return true if indexA, indexB both valid Defined in geometry3d/IndexedXYCollection.ts Line 73 Last Updated: 11 June, 2024