tentukan limit X mendekati 0 1- cos x/tan² 2x

lim   (1 - (1 - 2 sin² (x/2))) / tan² 2x
x->0
= lim  (2 sin² (x/2)) / tan² 2x
  x->0
= 2 (x²/4) / 4x²
= 1/8