Lg(1/2+x)=Lg(1/2x)
Lg(1/2+x)-Lg(1/2x)=0
Lg( (1/2+x)/(1/2x) )=0
Lg(x+x^2)=Lg1
x+x^2=1
x(1+x)=1
x=1 or 1+x=1
x=0
√50cos²(9π/8)-√50sin²(9π/8)=√50(cos²(9π/8)-sin²(9π/8))=
=√50cos(2*9π/8)=√50cos(9π/4)=√50cos(2π+π/4)=
=√50cos(π/4)=√50*√2/2=√100 /2=10/2=5
1.50/3=16,66
2.300/4=75
3.1/1000/100=0,00001
6, 27, 36;
50, 70, 100;
20, 140, 180.