Răspuns :
2^(2x+1)-3•2^x +1=0
2•2^(2x)-3•2^x +1=0
notam y=2^x; y>0
=>2•y²-3y+1=0
Δ=9-8=1
y1=(3+1)/4=1=> 2^x=1; x=0
y2=(3-1)/4=1/2 => 2^x=1/2; x= -1; (pentru ca 2^(-1)=1/2)
S={-1; 0}
2^(2x+1)-3•2^x +1=0
2•2^(2x)-3•2^x +1=0
notam y=2^x; y>0
=>2•y²-3y+1=0
Δ=9-8=1
y1=(3+1)/4=1=> 2^x=1; x=0
y2=(3-1)/4=1/2 => 2^x=1/2; x= -1; (pentru ca 2^(-1)=1/2)
S={-1; 0}