Question

Determine as raizes da função
x² - 6x + 8
a) (4, 2)
b) (8,4)
C) (-4,-2)
d) (8,-4)
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Answer 1

Explicação passo-a-passo:

$\Delta= b^{2} -4ac= (-6)^2-4*1*8= 4\\x=\frac{-b\pm \sqrt{\Delta} }{2a} \\x=\frac{6\pm \sqrt{4} }{2} \\\\x=\frac{6\pm 2}{2}\\\\x_1=\frac{6+2}{2} =4\\\\x_2=\frac{6-2}{2} =2$