The normal equations obtained fitting a straight line
y = ax + b by the method of least squares over n points
(x,y) are 4 = 4a + b and say = 120a + 246. Then nis
Answers
Answer:
C) 6
Description for Correct answer:
Σy=aΣx+nb...(1)
Σxy=aΣx2+bΣx...(2)
4=4a+b...(3)
Σxy=120a+24b...(4)
From (2) and (4)
Σx=24
Comparing RHS of (1) and (3)
aΣx+nb=4a+b=24a4a=nbb⇒n=6
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