Transcript The CAST Diagram

The graph of
y  sin x
y
1
0.5
0
-0.5
-1
180
360
x
The graph of
y  cos x
y
1
0.5
0
-0.5
-1
100
200
300
x
The graph of
y
y  tan x
20
10
0
-10
-20
180
360
x
The CAST Diagram
Sin only
positive
2nd
Quadrant
3rd
Tan only
positive
1st
All positive
Quadrant
4th
Quadrant Quadrant
Cos only
positive
Example
Given that  lies between 0° and 360° and that
sin  
indicate possible values of  on separate diagrams. State the
possible values of .
1
2
Example
Given that  lies between 0° and 360° and that
tan   3
indicate possible values of  on separate diagrams. State the possible
values of .
Example
Solve each of the following equations for
your answers correct to 2 decimal places
(i)
3 sin x  2
(ii) 1  4 cos x  0
(iii) 5  6 tan x  1

0  x  360
, giving
Example
1
2
Solve the equation cos x 
2
in the range
0  x  360 .