Pca, Principal Components, Dimensionality Reduction, Eigenvectors, Eigenvalue.
we have got two data points. [0.489925, 0.871765], [0.871765, -0.48993]. Both these points can be thought of as a vector from the origin and interestingly both are unit vectors i.e. their magnitude is 1. Proof = sqrt(a² + b²) = sqrt(0.489925² + 0.871765²) = 1, similarly for other data point.