=sin(2π+π/6)-cos(2π-π/6)+ctg(3π-π/4)=sinπ/6-cos(-π/6)+ctg(-π/4)=1/2-√3/2-1= -√3/2-1/2
7х/|х+3|
1) |х+3|>0
х+3>0
х>-3
2) |х+3|<0
-х-3<0
-х<3
х>-3
Ответ: х>-3
(√5+6√27) - (√5-6<span>√27) = </span>12√27
x^2+2sqrt22 = (12√27)^2 + 2√22 = 144*27 + 2√22 = 3888 + 2√22