# Basis of the intersection of two subspaces: ibasis

### 5.47.10 Basis of the intersection of two subspaces: ibasis

The ibasis command finds a basis for the intersection of two subspaces of ℝn.

- ibasis takes two arguments:
  L1 and L2, two lists of vectors generating two subspaces of ℝn.
- ibasis(L1,L2) returns a list of vectors forming a basis for the intersection of these two subspaces.

#### Example.

Input:

ibasis([[1,2]],[[2,4]])

Output:

⎧ ⎨ ⎩ | ⎡ ⎣ | 1,2 | ⎤ ⎦ | ⎫ ⎬ ⎭