S=S(от -π/3 до π/3)(cosx-0,5)dx=sinx-0,5x=sinπ/3-π/6-sin(-π/3)-π/6=2sinπ/3-π/3=
=2*√3/2-π/3=√3-π/3
3<a<4
5<b<6
--------------
8<a+b<10
16<2(a+b)<20
А) таблица: x|1|0|-1
y|4|5|6
б)таблица: x|1|0|-1
y|0|-1|-2
(×-14/×-15)-14/13=0
(13х-182-14х+210)/13×-195=0
(-×+28)/13×-195=0
-×+28=0
-×=-28
×=28