Orthogonal Projection

w = projVw + projVw

Plane V = span{e₁, e₂}
e₁
e₂

e₁, e₂ are an orthonormal basis of V (‖e₁‖ = ‖e₂‖ = 1, e₁ ⊥ e₂), so projV(w) = ⟨w, e₁⟩ e₁ + ⟨w, e₂⟩ e₂.


Vector w (not in V)
w

Decomposition

Legend
e₁ (basis of V)
e₂ (basis of V)
w
⟨w, e₁⟩ e₁
⟨w, e₂⟩ e₂
projV(w)
projV⊥(w)
V⊥ axis / construction
plane V

Drag colored sphere at vector tip to move it
Drag background to orbit  ·  scroll to zoom
Axes labelled x, y, z