1) sin x cos x - cos x =0 2) tan x cos x + cos x =0 3) sin ² x -1 =0 4) sin 2x -sin x =0 5) sin x = cos x 6)sin 2x - cos x=0 7)sec x =cosec x

Persamaan Trigonometri

1) sin x cos x - cos x = 0
cos x ( sin x - 1) = 0
cos x = 0 --> x= 0, 270 =  0, 3/2 π
sin x = 1 --> x = 90 = 1/2 π
HP x  = ( 0 ,  1/2 π, 3/2 π)

2) tan x cos x - cos x = 0
cos x ( tan x - 1) = 0
cos x = 0 --> x = 0 , 270 = 0, 3/2 π
tan x = 1 --> x = 45, 225 = 1/4 π, 5/4 π
HP x = (0 , 1/4 π, 3/2 π, 5/4 π)

3)  sin²  x - 1 = 0
sin² x = 1
sin x = 1  atau sin x = - 1
sin x = 1 --> x = 90 = 1/2 π
sin x = - 1 --> x = 270 = 3/2 π
HP x = (1/2 π, 3/2 π)

6) sin 2x - cos x  = 0
2 sin x cos x - cos x = 0
cos x (2  sin x - 1) = 0

cos x = 0 --> x= 1/2 π, 3/2 π

2 sin x  -1 = 0
sin x = 1/2  --> x = 1/6 π, 5/6 π

HP x = (1/6 π, 1/2 π, 5/6 π, 3/2 π)

5) sin x = cos x ..
cos x ( tan x) = cos x(1)
tan x = 1  --> x = 1/4 π , 5/4 π
HP x = (1/4 π, 5/4 π)

4) sin 2x - sin x = 0
2 sin x cos x  - sin x  = 0
sin x (2 cos x - 1)= 0
sin x = 0 --> x= 0 ,  2π

2 cos x - 1= 0
cos x =1/2 --> x = 1/3 π  , 5/3 π

HP x  = (0, 1/3 π, 5/3 π, 2π)

7) sec x  = cosec x 
sec x = sec (1/2 π - x)
x = 1/2 π - x
2x =1/2 π
x = 1/4 π