<math>
W_1 =\{\sum_{i=1}^m \alpha_i v_i \, : \, \forall i \, ; \alpha_i \in \mathbb{F} \}\\W_2 =\{\sum_{i=1}^ל k \alpha_i v_{m+i} \, : \, \forall i \, ; \alpha_i \in \mathbb{F} \}
</math>
אז
<math>W_1+W_2 = \{\sum_{i=1}^k \alpha_i v_i \, : \, \forall i \, ; \alpha_i \in \mathbb{F} \} </math>