5.2b Six Trigonometric Functions of Any Angle (Special Angles)

5.2b Six Trigonometric Functions of Any Angle 

(B) Special Angles

(1) Value of Special Angle 30° and 60°


(a) sin30°= 1 2            (b) cos30°= 3 2         (c) tan30°= 1 3 (d) sin60°= 3 2         (e) cos60°= 1 2            (f) tan60°= 3


(2) Value of Special Angle 45°


  (a)sin 45 o = 1 2       (b)cos 45 o = 1 2       (c)tan 45 o =1   


(3) Value of Special Angle 0°, 90°, 180°, 270°, 360°

(a) y = sin x


x
0o
90o
180o
270o
360o
sin
0
1
0
-1
0

(b) y = cos x




x
0o
90o
180o
270o
360o
cos 
1
0
-1
0
1


(c) y = tan x


x
0o
90o
180o
270o
360o
tan 
0
¥
0
¥
0