### 27.11.1 Checking whether object in space is in another object

See Section 26.15.1 for checking elements in 2D geometry.

The is_element command determines whether or not a geometric object is contained in another.

- is_element takes two arguments: G,H, two geometric objects.
- is_element(G,H) returns 1 if G is contained in H and 0 otherwise.

#### Examples

P:=plane([0,0,0],[1,2,-3],[1,1,-2]); is_element(point(2,3,-5),P)

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L,P:=line([2,3,-2],[-1,-1,-1]),plane([-1,-1,-1],[1,2,-3],[1,1,-2]); is_element(L,P)

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