Question
Find the exact solutions of the equation In The interval.. Sin 2x -sin x=0
Answers
sin 2 x = sin x when x = 0, 180, 360 etc
sin 2x - sinx =0
2sinx cosx - sinx = 0
sinx(2cosx - 1) = 0
sinx = 0 or cosx = 1/2
for sinx = 0
x = 0, 180°, 360°
for cosx = 1/2
x = 60° , 300°
so for 0 ≤ x ≤ 360°
x = 0, 60, 180, 300, 360
in radians:
x = 0 , π/3 , π , 5π/3 , 2π
2sinx cosx - sinx = 0
sinx(2cosx - 1) = 0
sinx = 0 or cosx = 1/2
for sinx = 0
x = 0, 180°, 360°
for cosx = 1/2
x = 60° , 300°
so for 0 ≤ x ≤ 360°
x = 0, 60, 180, 300, 360
in radians:
x = 0 , π/3 , π , 5π/3 , 2π