Derive equation (11.55).

(a) Square and sum the residuals of equation (11.54) to obtain

(b) Multiply the middle term by

Explain why the result can be expressed as

(c) Combine this new expression for the second term to the right of the equality in part a with the last term to prove equation (11.55).

Transcribed Image Text:

i=1 xx 11x) = i=l n i=1 i=1