10.3 Review

Here is a review problem from 10.3

x^4+x^2-12=0
(x^2)2 u=x^2
u^2+u-12
(u+4)(u-3)
u=-4 and u=3
x^2=-4 and x^2=3
x= SQRT-4 and x=SQRT3
x=2i and x=SQRT3