1) =log5 5³=3
2)lg 0.01=-2
3) log2 (68/17)=log2 4=2
39x³y/26x²y²=3x/2y
5y/(y²-2y)=5y/y(y-2)=5/(y-2)
3x²-5x-2=0
D=25-4×3×(-2)=49,√49=7
D>0,два корня
x1=(5-7)/6=-2/6=-1/3
x2=(5+7)/6=2
Ответ:-1/3;2
(2*sin⁴(x/2)-1)*(1/cos⁴(x/2)=2
2*sin⁴(x/2)-1=2*cos⁴(x/2)
2*cos⁴(x/2)-2*sin⁴(x/2)=-1
2*(cos⁴(x/2)-sin⁴(x/2)=-1
(cos²(x/2)-sin²(x/2))*(cos²(x/2)+sin²(x/2))=-1/2
cosx*1=-1/2
cosx=-1/2
x₁=2π/3+2πn x₂=4π/3+2πn.