Question

Me ajude na biquadrada: x^4+x²+4=6x²

Answer 1

x² = y
y² + y -6y + 4 = 0
y² -5y +4 = 0

Soma = 5, produto 4, logo y1 = 1, y2 = 4

x² = 1
x= +- 1

x² = 4
x = +-2

Answer 2

x⁴ + x² + 4 = 6x²
x⁴ + x² + 4 - 6x² = 0
x⁴ - 5x² + 4 = 0<<<<< y² - 5y + 4 = 0

Bhaskara:
b² - 4ac
-5² -4.1.4
25 - 16
9 = Δ

-b+/- √Δ /2a
-(-5) +/- √9 /2.1
5 +/- 3 / 2

y1 = 5+3/2 = 8/2 = 4
y2 = 5-3/2 = 2/2 = 1

x1 = √y1 
x1 = √4 = 2

x2 = - √y1
x2 = -√4 = - 2

x3 = √y2 
x3 = √1 = 1

x4 = - √y2
x4 = - √1 = -1