lim x menuju phi cos 2x-1 / sin x?

lim x→π (cos 2x - 1) / (sin x)
cos 2x = 1 - 2 sin² x
= lim x→π (1 - 2 sin² x - 1) / (sin x)
= lim x→π (-2 sin x)
= lim x→π (-2 sin π)
= 0