Question

resolva a equação biquadrada em IR

​

Answer 1

(x² -1)² + (x² -5)² = 40

x⁴-2x²+1 + x⁴-10x²+25 - 40 = 0

2x⁴ -12x² -14 = 0 ===> :(2)

x⁴ - 6x² - 7 = 0

∆= 36 +28=64 => √∆=8

x = -b±√∆/2a

x = 6±8/2

x = 6+8/2 = 7 ===> x' = ±√7 ✓

x = 6-8/2 = -1 ===> x" = √-1 = { }