Question

Срочно нужно сделать
плиз помогите!!!!!!!!!!!!!!!!

Answer 1

11. log₃7·log₇3a=log₃7·log₃3a / log₃7=log₃3a=log₃3+log₃a=
=1+log₃3√3=1+log₃3^(3/2)=1+3/2=5/2=2.5;
12. log₂8-log₃9=log₂2³-log₃3²=3-2=1;
13. log₁/₃ (x-4)=-1/2;⇒
x-4>0;x>4;
log₃⁻¹(x-4)=-1/2;
-log₃(x-4)=-1/2;
log₃(x-4)=1/2;⇒
√3=x-4;
x=4+√3;