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Center of mass of a triangle
(barycentre)
The three medians of a triangle all meet at a single
point. This point is called the “center of mass” (or
barycentre).
The center of mass divides each line in half.
For a triangle with corner points , and ,
the center of mass is given:
Program
?→ X:?→ Y:X → A:Y → B:?→ X:?→ Y:X → C:Y → D:?→ X:?→ Y:
(A + C + X)÷3→ X:(B + D + Y)÷3→ Y:X Y < 67 STEP >
INPUT X, Y (first time):
A
(
X, Y
) X, Y(second time) :
B
(
X, Y
) X, Y(third time) : C(
X, Y
)
OUTPUT X, Y: center of mass
P(X, Y)
Execution Example:
The center of mass for a triangle with corners A(1,0),B(0,3) and C(-1,0) is P(0,1).
A
B
C
P
O
AB C
OP
OA OB OC++
3
---------------------------------------=
ON
MODE MODE MODE
1
PRGM
MODE
1
COMP
1
P1
Prog
1
S A
D R
P1
P2 P3 P4
G
1
EXE
0
EXE
S A
D R
P1
P2 P3 P4
G
0
EXE
3
EXE
1
EXE
0
EXE
Disp
S A
D R
P1
P2 P3 P4
G
EXE
S A
D R
P1
P2 P3 P4
G
関数電卓事例集 .book 28 ページ 2002年9月2日 月曜日 午後6時51分