let F be Field; for E being FieldExtension of F
for K being F -extending FieldExtension of F
for BE being non empty finite linearly-independent Subset of (VecSp (E,F))
for BK being non empty finite linearly-independent Subset of (VecSp (K,E)) holds card (Base (BE,BK)) = (card BE) * (card BK)
let E be FieldExtension of F; for K being F -extending FieldExtension of F
for BE being non empty finite linearly-independent Subset of (VecSp (E,F))
for BK being non empty finite linearly-independent Subset of (VecSp (K,E)) holds card (Base (BE,BK)) = (card BE) * (card BK)
let K be F -extending FieldExtension of F; for BE being non empty finite linearly-independent Subset of (VecSp (E,F))
for BK being non empty finite linearly-independent Subset of (VecSp (K,E)) holds card (Base (BE,BK)) = (card BE) * (card BK)
let BE be non empty finite linearly-independent Subset of (VecSp (E,F)); for BK being non empty finite linearly-independent Subset of (VecSp (K,E)) holds card (Base (BE,BK)) = (card BE) * (card BK)
let BK be non empty finite linearly-independent Subset of (VecSp (K,E)); card (Base (BE,BK)) = (card BE) * (card BK)
thus (card BE) * (card BK) =
card [:BE,BK:]
by CARD_2:46
.=
card (Base (BE,BK))
by BE1
; verum