Răspuns:
[tex]\sqrt{x-1} =x-3\\ \\(\sqrt{x-1})^{2}=(x-3)^{2} \\ \\ (x-1)=x^{2}-6x+9\\ \\ x^{2} -6x+9+1-x=0\\ \\ x^{2} -7x+10=0\\ delta=b^{2}-4ac=49-40=9\\ \\ x_{1}=(-b+\sqrt{delta})/2a=(7+\sqrt{9}/2=(7+3)/2=5\\ \\x_{2}=(-b-\sqrt{delta})/2a=(7-\sqrt{9}/2=(7-3)/2=2[/tex]
Explicație pas cu pas: