Every nth degree equation has n solutions. Some solutions may be double roots (i.e. (x-1)(x-1) = 0). The graph may only pass through the x-axis (where y = 0, which would be a solutions) less than n times. When this occurs, you get an imaginary solution, which is what i is.

]]>And I guess majicWaffle is right,

also (i, -2i) and (-i, 2i), whatever these complex thingys mean, I don't remember.

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

(x^2 - 4)(x^2 +1) = 0

x^2 - 4 = 0 x^2 + 1 = 0

x^2 = 4 x^2 = -1

x = +- 2 x = +- i

I got y by itself then I got...

2/x = ±√(x²-3)

I'm stuck at 4 = x^4-3x²

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