Respostas

2013-12-14T22:13:25-02:00
X^4-5x^2+4

x²=y

y^2-5y+4=0
Δ = b² -4ac
Δ = (-5)² -4 *1 * 4
Δ = 25 -16
Δ = 9
x' = (-b + √∆)/ 2a
(-(-5) + 3)/2 * 1
(5 + 3)/2
8/2= 4
x'' = (-b - √∆)/ 2a
(-(-5) - 3)/2 * 1
(5 - 3)/2
2/2= 1

x
²=y
x
²=4
x= + - √4
x=+-2

x²=y
x=+-√1
x=+-1

S= {-2,-1,1,2}
1 5 1