(x-2)^2+4x=1
x^2-4x+4+4x-1=0
x^2+3=0
x^2=-3
нет решений
2x²-4x+1=0
D=16-8=8
x₁=(4-√8)/4=(4-2√2)/4=1-0.5√2
x₂=1+0.5√2
+ - +
-------- 1-0.5√2 ----------------- 1+0.5√2 --------------
\\\\\\\\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\\\\\\
x∈(-∞; 1-0.5√2]U[1+0.5√2; +∞)
""""""""""""""""""""""""""""""""""""""""""""""""""""