Question

Решите уравнение
√x-4 = √8-x

Answer 1

$sqrt{T}=sqrt{U} textless - textgreater left { {{T=U} atop {T geq 0}} right. \\ sqrt{x-4}=sqrt{8-x} textless - textgreater left { {{x-4=8-x} atop {x-4 geq 0}} right. \\ left { {{2x=12} atop {x geq 4}} right. \\ left { {{x=6} atop {x geq 4}} right. \\ x=6$

Answer 2

{x+8≥0⇒x≥-8
{x-4≥0⇒x≥4
x∈[4;∞)
(x-4)²=(√x+8)²
x²-8x+16=x+8
x²-9x+8=0
x1+x2=9 U x1*x2=8
x1=1 не удов усл
х2=8