–18–
#051
A = – B
(
)
– C
(
)
n
Σy
n
Σx
n
Σx
2
B =
Sxx
.
Sx
2
x
2
– (Sxx
2
)
2
Sxy
.
Sx
2
x
2
– Sx
2
y
.
Sxx
2
C =
Sxx
.
Sx
2
x
2
– (Sxx
2
)
2
Sx
2
y
.
Sxx
– S
xy
.
Sxx
2
(Σx)
2
Sxx = Σx
2
–
n
Sxy = Σxy –
n
(Σx
.
Σy)
Sxx
2
= Σx
3
–
n
(Σx
.
Σx
2
)
Sx
2
x
2
= Σx
4
–
n
(Σx
2
)
2
Sx
2
y = Σx
2
y –
n
(Σx
2
.
Σy
)
m
1 =
2C
– B
+
B
2
–
4
C
(
A
– y
)
m
2 =
2C
– B –
B
2
– 4C
(
A
– y
)
= A + Bx + Cx
2