MizoriesKun lg(x^2+9)+lg2=1+lg(x+1)
ОДЗ x+1>0  х>-1
lg2*(x^2+9)=lg10*(x+1)
2*(x^2+9)=10*(x+1)
2x²+18-10x-10=0
2x²-10x+8=0  |2
x²-5x+4=0
D=25-16=9        √D=3
x₁=(5+3)/2=4
x₂=(5-3)/2=1 

|∑x₁,x₂|=|4+1|=5

log₈ log₄ log₂ (8⁴*4²)=log₈ log₄ log₂ ((2³)⁴*(2²)²)=log₈ log₄ log₂2¹²⁺⁴=

=log₈ log₄ log₂2¹⁶=log₈ log₄ 16=log₈ log₄ 4²=log₈ 2 =log₂³2 = (1/3)*log₂2 =1/3