beautypg.com

Texas Instruments TITANIUM TI-89 User Manual

Page 778

background image

Activities

778

3. 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

a

for the unknown speed of the

current. Use the value

b

for the speed of

the 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.

4. Define function

p2r

.

Enter:

Define p2r(x)=[x[1,1]*cos(x[1,2]),

x[1,1]*sin(x[1,2])]