Question

Solve:

x⁴ – 2x² – 3 = 0

Answer 1

x⁴ – 2x² – 3 = 0

`=>` x⁴ – 3x² + x² – 3 = 0

`=>` x²(x² – 3) + 1(x² – 3) = 0

`=>` (x² – 3)(x² + 1) = 0

If x² – 3 = 0 or x² + 1 = 0

`=>` x² = 3 or x² = –1  ...(Reject)

`=> x = +-sqrt3`