+4 
Please show steps or explain as I would like to learn how to solve future questions. Thank you :)
+128407 1. Note that sin ( x - pi) = sin x cos (pi ) - sin( pi ) cos x = sinx * (-1) - 0 * cosx = -sin x
So
2sin ( x -pi ) - 1 = 0
2 (-sin x) - 1 = 0
-2sin x = 1
sin x = -1/2
x = 7pi / 6 + n* 2pi and x = 11pi/6 + n* 2pi
Where n is an integer
+128407 2. -3cos ( pi - 2x) = 1
Note
cos (pi -2x) = cos (pi) cos (2x) + sin (pi) * sin (2x) = -1cos (2x) + 0* sin (2x) = -cos (2x)
So
-3 (-cos (2x) ) = 1
3 cos (2x) = 1
cos (2x) = 1/3
arccos (1/3) = x ≈ .123 rads
So
2x = 1.23
x = 1.23 / 2 ≈ .615 rads
So x = [ .615 + 2pi * n ] rads where n is an integer
Also
x = [ (2pi - .615 ) + 2pi*n] rads ≈ [ 5.668 + 2pi*n ] rads where n is an integer
