Question

(x+2)^4+(x+2)^2-12=0

Answer 1

$(x+2)^4+(x+2)^2-12=0$

$(x+2)^2=t,t geq 0$

$t^2+t-12=0$

$D=1+48=49$

$t_1=frac{1-7}2=3$

$t_2=frac{-1-7}2=-4$

$(x+2)^2=3$

$x_1=sqrt3-2$

$x_2=-sqrt3-2$