7,8(6,3+13,7)=7,8*20=78*2=156
ctg(x/2) - tg(x/2) - 2*tg(x) = 4
<span>log3;x^2 - log3^2;(-x) + 3=0</span>
Б
x(x²-4x+3)>0
x(x-1)(x-3)>0
x=0 x=1 x=3
_ + _ +
------------------(0)-----------(1)----------------(3)---------------------
x∈(0;1) U (3;∞)
x^4-1<0
(x-1)(x+1)(t²+1)<0
x=1 x=-1
+ _ +
-----------------(-1)-----------------(1)-----------------
x∈(-1;1)