( x + 3 )^4 - 3(x + 3 )^2 -

( х + 3 )^4 - 3( х + 3 )^2 - 4 = 0
( х + 3 )^2 = а ; а gt; 0
а^2 - 3а - 4 = 0
D = 9 + 16 = 25 ; V D = 5
a1 = ( 3 + 5 ) : 2 = 4
a2 = ( 3 - 5 ) : 2 = - 1 ( lt; 0 )
( x + 3 )^2 = 4
x^2 + 6x + 9 - 4 = 0
x^2 + 6x + 5 = 0
D = 36 - 20 = 16 ; V D = 4
x1 = ( - 6 + 4 ) : 2 = - 1
x2 = ( - 6 - 4 ) : 2 = - 5
Ответ : ( - 1 ) ; ( - 5 )

Х+3=а
а4-3а2-4=0
а2=б
б2-3б-4=0
д=9-4*1*(-4)=25
б1=(3-5)/2=-1
б2=(3+5)/2=4
а2=-1 корней нет
а2=4
а1=2
а2=-2
х+3=2
х=2-3
х1=-1
х+3=-2
х2=-5