9^х+2-30*3^х+1=0
3^x=t t > 0 9^(x+2)=9^x*9^2=81t^2 81t^2-30t+1=0 D=900-4*81=900-324=576=24^2 t=(30-24)/162=6/162=1/27 или t=(30+24)/162=54/162=1/3 3^x=1/27 3^x=3^(-3) x=-3 или 3^x=1/3 3^x=3^(-1) x=-1