Question

Решите!!!
$1)x ^{4} - 2x {}^{2} - 3 = 0 \ 2)3x {}^{2} - x {}^{3} = 0$

Answer 1

$1)quad x^4-2x^2-3=0\\t=x^2 geq 0; ,; ; ; t^2-2t-3=0; ,\\t_1=-1; ,; ; t_2=3; ; (teorema; Vieta)\\t_1=-1 textless 0\\t_2=3quad to ; ; x^2=3; ; ; to quad underline {x_{1,2}=pm sqrt3}\\\2); ; ; 3x^2-x^3=0\\x^2cdot (3-x)=0\\x^2=0; ; to ; ; ; underline {x_1=0}\\ 3-x=0; ; to ; ; underline {x_2=3}$