Answer:
Step-by-step explanation:
This equation looks complicated.We have to make it easier
let's say x^2/3 = t and x^4/3 = t^2
t^2-10t+21=0 [ we can factorize this equation as a (t-3)(t-7) ]
(t-3)(t-7)=0 [ that means , t can be 3 or 7 ]
But don't forget we have to find x not t so,
t=x^2/3=3 ∛ x^2 = 3 x^2 = 9 x=3 or x= -3
t=x^2/3=7 ∛x^2 = 7 x^2 = 343 x ~18.5 or x ~ -18.5