Question

Помогите с уравнением

Answer 1

lgx=a
a²-a-2=0
a1+a2=1 U a1*a2=-2
a1=2⇒lgx=2⇒x=10²=100
a2=-1⇒lgx=-1⇒x=10^-1=0,1

Answer 2

$lgx= alpha \ alpha ^{2} - alpha -2=0 \ alpha _{1} + alpha _{2} =1 \ alpha _{1} * alpha _{2}=-2 \ alpha _{1} =2 \ x= 10^{2} =100 \ alpha _{2} =-1 \ x=0.1$