Consider the XOR problem where there are four training points:

(1, 1, –), (1,0, +), (0, 1, +), (0, 0, –)

Transform the data into the following feature space:

ϕ(x ₁ , x ₂ ) – (1, √x ₁ , √2x ₂ , √2x ₁ x ₂ , x ₁ ² , x ₂ ² )

Find the maximum margin linear decision boundary in the transformed space.