Question

solve x^4+4x^2-12=0

Answer 1

Bring the -12 to the other side of the equation so you have

x^4-4x^2=12

factorise the left hand side taking an x^2 out

then solve the remaining quadratic

Answer 2

hint : x^2=a

Answer 3

then solve quadratic a^2+4a-12=0

Answer 4

(a-2)(a+6)=0

Answer 5

anybody there ?

Answer 6

a=2 --->x^2=2 2 root
a=-6 --->x^2=-6 no root