Question

Solve x^4+3x^2-4=0

please show work, thank you :)

Answer 1

x^4 + 3x^2 - 4 = 0
(x^2 - 1))(x^2 + 4) = 0
x^2 - 1 = 0 giving x = 1 and x = -1

x^2 + 4 = 0 giving x^2 = -4 so x = +2i and -2i.

Answer 2

x^4+3x^2=4
x^2(x^2+3)=4
x=1 or 2