let F be Field; :: thesis: for S being OrtSp of F
for b, a, c being Element of S st not a _|_ & a _|_ holds
ProJ a,b,c = 1_ F
let S be OrtSp of F; :: thesis: for b, a, c being Element of S st not a _|_ & a _|_ holds
ProJ a,b,c = 1_ F
let b, a, c be Element of S; :: thesis: ( not a _|_ & a _|_ implies ProJ a,b,c = 1_ F )
assume that
A1: not a _|_ and
A2: a _|_ ; :: thesis: ProJ a,b,c = 1_ F
( a _|_ & a _|_ ) by A1, A2, Th24, VECTSP_1:def 29;
hence ProJ a,b,c = 1_ F by A1, Th20; :: thesis: verum