Respostas

2013-12-12T14:34:30-02:00
X²-2x=2x-4
x-2x-2x=-4
x²-4x=-4
x²-4x+4=0
Δ = b² -4ac
Δ = (-4)² -4 *1 * 4
Δ= 16 -16
Δ = 0
x' = (-b + √∆)/ 2a
(-(-4) + 0)/2 * 1
(4 + 0)/2
4/2= 2
x'' = (-b - √∆)/ 2a
(-(-4) - 0)/2 * 1
(4 - 0)/2
4/2= 2

S={2,2}.

2013-12-12T14:36:19-02:00
X²-4x+4 = 0
Delta = 16 - 4*1*4
Delta = 16-16
Delta = 0

X' = - -(4) + 0 / 2
X' = 4/2 = 2