Casio fx-570MS - Manual (Page 41)

– 38 –
Vector Problems
( fx-570MS/fx-991MS only)
Express c
→
= (12, –5) in the form c
→
= s a
→
+ t b
→
when a
→
= (2, 1),
b
→
= (–3, 4).
Though this is a vector problem, it can be solved
by solving the following simultaneous equations
for each component.
2s – 3t = 12
s + 4t = –5
{
1 .
Select the EQN Mode and specify 2 as the number of unknowns.
F F F 1
(Unknowns?) 2
2 .
Input the function and store it.
(a1?) 2 =
(b1?)
D
3
=
(c1?) 12 =
(a2?) 1
=
(b2?) 4 =
(c2?) D 5 =
3 .
This shows that the solutions of the simultaneous equations are 3 and 2.
The above tells us that c
→
=3 a
→
– 2 b
→
.
Example 1 Example 1
Explanation Explanation
Operation
a = (2,1)
c = (12, –5) = sa + t b
b = (–3,4)
t b
sa
] [