3^x-8=3^2/3^x
3^x>8
3^x=t
t-8=9/t
t^2-8t-9=0
t=9 3^x=9 x=2
1-x^2+1+2sqrt(1-x^2)<3-x^2
2sqrt(1-x^2)<1
4-4x^2<1
4x^2>3 x^2>3/4
x>sqrt(3)/2 U x<-sqrt(3)/2
-1<=x<=1
[-1;sqrt(3)/2[ U ]sqrt(3)/2;1]
