15/(t-2) =t ; t=3^(x) > 0
15 =t² -2t ;
t² -2t -15 =0 ;
t=1±√(1+15) =1±4;
t₁ = -3; не решение * * * 3^x = -3
t₂ =5.
3^x =5;
x = Loq_3 5.
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15/(3^x +2) =3^x.
15/(t+2) =t ;
t² +2t -15 =0;
t₁ = -5;
t₂ =3 ;
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3^x=3;
x =1.