Beachte: 10^{x+2} = 10^x * 10^2 = 10^x*100
0.1^x - 10^{x+2} = 10^x - 0.1^{x+2}
1/10^x - 100*10^x = 10^x - 1/(10^{x+2})
1/10^x - 100*10^x = 10^x - 1/(100*10^{x})
10^x = u . Substituieren, wobei u> 0
1/u - 100u = u - 1/(100u) |*u
1 - 100u^2 = u^2 - 1/100
1 + 1/100 = 101u^2
1.01 = 101 u^2
0.01 = u^2
u = ± 0.1 . nur die positive Lösung kommt in Frage.
u= 10^x = 0.1 = 10^{-1}
10^x = 10^{-1} |Exponenten vergleich
x = -1
Kontrolle:
0.1^x - 10^{x+2} = 10^x - 0.1^{x+2}
0.1^{-1} - 10^{-1+2} = 10^{-1} - 0.1^{-1+2}
10 - 10 =0= 1/10 - 1/10 =0 ok.