Question

x²-2,5+1=0 equação de 2° grau

Answer 1

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x²-2,5x+1=0

a=1
b=-2,5
c=1

Δ=b²-4ac
Δ=(-2,5)²-4(1)(1)
Δ=6,25-4
Δ=2,25

$x= \frac{-b\pm \sqrt{\triangle} }{2a} = \frac{-(-2,5)\pm \sqrt{2,25} }{2} = \frac{2,5\pm1,5}{2} \\ \\ x'= \frac{2,5+1,5}{2}= \frac{4}{2} =2 \\ \\ x"= \frac{2,5-1,5}{2} = \frac{1}{2}=0,5 \\ \\ S= \{0,5;2\}$

Answer 2

x² - 2,5x + 1 = 0

Δ = (2,5)² - 4.1.1 = 6,25 - 4 = 2,25

x' = [-(-2,5) + √2,25]/2.1 = 2,5 + 1,5/2 = 4/2 = 2

x" = [-(-2,5) - √2,25]/2.1 = 2,5 - 1,5/2 = 2,5 - 1,5/2 = 1/2 = 0,5