Question

f(x) =-x²+5x-3 sendo f:R--->R​

Answer 1

Resposta:

Explicação passo-a-passo:

a = - 1

b = 5

c = - 3

Δ = b² - 4 a c

Δ = 5² - 4 . (-1) . (-3)

Δ = 25 - 12 = 13

$x = \frac{- b \frac{+}{-} \sqrt{\delta } }{2 a} =\\\\x = \frac{- 5 \frac{+}{-} \sqrt{13 } }{2 (-1)} =\\x = \frac{- 5 \frac{+}{-} \sqrt{13 } }{-2 } =\\x' = \frac{- 5 - \sqrt{13 } }{-2 } = \frac{5 + \sqrt{13 } }{2 }\\\\x'' = \frac{- 5 + \sqrt{13 } }{-2 } = \frac{ 5 - \sqrt{13 } }{2 }$