7T
tg 2*   l!hv_ ^-2 _       2tg2 (f - x) cos2 (f - x)
lim tg 2x tg--i   = lim -=-       =  lim -=—cos —=---- = lim
V4      / —A—T      X-+1--4—t--t±—cos22x
„sin2( ^—2:)        o \
2   ,)4   {cos2í^-x) o • 2 z* \
cos^f-z) U y 2 Slil     4-I LH
= lim---—-= lim--- =
x^t\ COS2 2x x^t\       cos2 2x
ľ h       2-2 sin (f - x) cos (f - x)           sin (f - 2x) VH       cos (f - 2x) (-2) = hm -—---—-- = hm -—-- = hm
2 • 2 cos 2x sin 2x x^\     sin4x x^\ cos(4x)(4)
-2 _ 1 Ä ~ 2
1