To find the value of x, we can use the trigonometric identity:
sin(pi + x) = sin(pi)cos(x) + cos(pi)sin(x)
Since sin(pi) = 0 and cos(pi) = -1, we have:
sin(pi + x) = 0cos(x) + (-1)sin(x)sin(pi + x) = -sin(x)
Now, we need to find where cos(-pi/3) = -sin(x). We know that cos(-pi/3) = cos(pi/3), so we have:
cos(pi/3) = -sin(x)cos(60 degrees) = -sin(x)1/2 = -sin(x)
Since sin(30 degrees) = 1/2, we have x = -30 degrees (or -pi/6 in radians).
To find the value of x, we can use the trigonometric identity:
sin(pi + x) = sin(pi)cos(x) + cos(pi)sin(x)
Since sin(pi) = 0 and cos(pi) = -1, we have:
sin(pi + x) = 0cos(x) + (-1)sin(x)
sin(pi + x) = -sin(x)
Now, we need to find where cos(-pi/3) = -sin(x). We know that cos(-pi/3) = cos(pi/3), so we have:
cos(pi/3) = -sin(x)
cos(60 degrees) = -sin(x)
1/2 = -sin(x)
Since sin(30 degrees) = 1/2, we have x = -30 degrees (or -pi/6 in radians).