Respostas

2013-09-25T16:18:21-03:00
A) y = x² - 25
Delta = (0)^2 - 4(1)(-25)
Delta = 100
x¹ = 5
x²=-5

b) x²-10x+21
Delta = (-10)² -4(1)(21)
Delta = 64
x¹ = 9
x²=1

c) y = -x²+6x - multiplica por -1 trocando o sinal.
Delta = (-6)²-4(1)(0)
Delta = 36
x¹=6
x²=0

d) y = -x²+ x + 6
Delta = (1)²-4(-1)(6)
Delta = 25
x¹=-2
x²=3

e)9x²-1
Delta=(0)²-4(9)(-1)
Delta=36
x¹=1/3
x²=-1/3

f) y = 6x² + 6x
Delta=(6)²-4(6)(0)
Delta=36
x¹=0
x²=-1
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