Răspuns:
observi ca( 2+√3)(2-√3)=4-1=1=>
2-√3=1/(2+√3)=>
(2-√3)ˣ=1/(2+√3)ˣ
Notam (2-√3)ˣ=y y>0
y+1/y=4
y²+1=4y
y²-4y+1=0
Δ=16-4=12
y1=(4-√12)2=(4-2√3)/2=2-√3=>
(2-√3)ˣ=2-√3=>
x=1
y2=(4+√12)/2=2+√3)=>
(2-√3)ˣ=2+√3=1/(2-√3)=>
x `=-1
Deci S={-1;+1}
Explicație pas cu pas: