Texas Instruments TI-89 Titanium Short User Manual page 118

1. Set the modes for
screen. (Show angles in degrees instead of
radians and display all digits with a floating
decimal point.)
Press: 3 D D D. On the Angle option,
select
2:DEGREE
option, select
2. Enter vectors describing the initial path of
the boat, water current, and resultant path
of the boat.
Store these vectors as i, c, and r. Use the
value for the unknown speed of the
a
current. Use the value
boat.
Enter:
!
¡
[20,80 ] i
!
¡
[a,0 ] c
!
[b,60°] r
Vectors are commonly written in either polar or
rectangular form, so it is useful to convert polar
vectors into rectangular form.
3. Define function
Enter:
Define p2r(x)=[x[1,1]*cos(x[1,2]),
x[1,1]*sin(x[1,2])]
112
as shown in this
Page 1
. On the Display Digits
.
E:FLOAT
for the speed of the
b
.
p2r
Activities