Prove the following equalities. Please show all the steps in the derivation. a. Σ(i=1 to n) (xi - x̄)(yi - ȳ) = Σ(i=1 to n) xi(yi - ȳ) b. Σ(i=1 to n) (xi - x̄)(yi - ȳ) = Σ(i=1 to n) xiyi - n(x̄ȳ) Summations apply to entire side of equation.
Added by Benjamin M.
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We want to show that $\sum_{x=1}^n (x_i - \bar{x})(y_i - \bar{y}) = \sum_{x=1}^n x_i(y_i - \bar{y})$. Show more…
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