According to (1.17), lei = 0 when regression model (1.1) is fitted to a set of n cases by the method of least squares. is it also true that l e: i = o? comment.

solution:

\sum ei =0

that is  

\sum (yi-yiˆ)=0

means,

\sumyi = \sum yiˆ

yi = \alpha +\beta xi+ei

yiˆ=\alphaˆ+\betaˆxi

so,

\sumei=0

hence proved

the answer is:

the lateral area is equal to

to find the lateral area of the square pyramid, first we need to find the perimeter of the base, and then, find the lateral area using the following formulas:

where,

s, is the base length

slant height, is the height of a the side of the pyramid

we are given:

now, calculating the perimeter of the base, we have:

then, calculating the lateral area:

hence, we have that the lateral area is equal to

have a nice day!