題目 Problem Let f(β)=∑i=1n(yi−1−βxi+2xi)2.f(\beta)=\sum_{i=1}^n\left(y_i-1-\beta x_i+2x_i\right)^2.f(β)=i=1∑n(yi−1−βxi+2xi)2. Suppose that ∑i=1nxi=−5\sum_{i=1}^n x_i=-5∑i=1nxi=−5, ∑i=1nyi=5\sum_{i=1}^n y_i=5∑i=1nyi=5, ∑i=1nxi2=15\sum_{i=1}^n x_i^2=15∑i=1nxi2=15, and ∑i=1nxiyi=10\sum_{i=1}^n x_i y_i=10∑i=1nxiyi=10. Find β\betaβ that corresponds to the minimum of fff. (a) 2/32/32/3 (b) 4/34/34/3 (c) 8/38/38/3 (d) 7/37/37/3 (e) None of the above. 解答 待補。
