Question

Untuk 0 =< x =< 360
Tentukan tan 3x = cot x
Dan cosec (x+10) = 2


Pakai caranya.

Answer 1

Tan 3x = cot x
tan 3x= tan (90- x)
3x = 90- x
4x = 90 + k. 180
x= 22,5 + k. 45
k = 0,1,2,3,4,5,6,7,8....
k = 0--> x= 22,5
k = 1 --> x = 67,5
k = 2 --> x= 112,5
k = 3 --> x = 157,5
k = 4 --> x = 202.5
k = 5--> x = 247,5
k = 6--> x = 292,5
k = 7 --> x = 337,5
 
2) cosec x = 1/sin x --> sin x = 1/cosec x
cosec(x+10)= 2
1/cosec(x+10) =1/2 --> sin (x+10) = 1/2 
a) sin(x+10) = 1/2 = sin 30
x + 10 = 30
x = 20
b) sin (x+10) = 1/2 = sin 150
x + 10 = 150
x = 140